agora inbox for pgsql-hackers@postgresql.orghelp / color / mirror / Atom feed
[PATCH v44 07/10] Split cluster.h to create repack_internal.h 354+ 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; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v44 07/10] Split cluster.h to create repack_internal.h @ 2026-03-24 14:09 Álvaro Herrera <alvherre@kurilemu.de> 0 siblings, 0 replies; 354+ messages in thread From: Álvaro Herrera @ 2026-03-24 14:09 UTC (permalink / raw) Most of the details of concurrent repack are only needed by pgoutput_repack; and they have a nasty effect on headers included by cluster.h (used by several high-profile places), so isolate that for cleanliness. Also, change_useless_for_repack() is better declared in decode.h. --- src/backend/commands/cluster.c | 128 ++++++++++-------- src/backend/postmaster/bgworker.c | 2 +- .../pgoutput_repack/pgoutput_repack.c | 13 +- src/include/commands/cluster.h | 57 +------- src/include/commands/repack_internal.h | 59 ++++++++ src/include/replication/decode.h | 4 + 6 files changed, 147 insertions(+), 116 deletions(-) create mode 100644 src/include/commands/repack_internal.h diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 75556cbdafb..2c3058ba10d 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -59,6 +59,7 @@ #include "commands/cluster.h" #include "commands/defrem.h" #include "commands/progress.h" +#include "commands/repack_internal.h" #include "commands/tablecmds.h" #include "commands/vacuum.h" #include "executor/executor.h" @@ -205,17 +206,11 @@ typedef struct DecodingWorkerShared char error_queue[FLEXIBLE_ARRAY_MEMBER]; } DecodingWorkerShared; -/* - * Generate worker's output file name. If relations of the same 'relid' happen - * to be processed at the same time, they must be from different databases and - * therefore different backends must be involved. (PID is already present in - * the fileset name.) - */ -static inline void -DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) -{ - snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); -} +/* Is this process a REPACK worker? */ +static bool is_repack_worker = false; + +static pid_t backend_pid; +static ProcNumber backend_proc_number; /* * Backend-local information to control the decoding worker. @@ -241,6 +236,7 @@ static DecodingWorker *decoding_worker = NULL; */ volatile sig_atomic_t RepackMessagePending = false; +static LOCKMODE RepackLockLevel(bool concurrent); static bool cluster_rel_recheck(RepackCommand cmd, Relation OldHeap, Oid indexOid, Oid userid, LOCKMODE lmode, int options); @@ -298,12 +294,16 @@ static Relation process_single_relation(RepackStmt *stmt, ClusterParams *params); static Oid determine_clustered_index(Relation rel, bool usingindex, const char *indexname); -static void start_decoding_worker(Oid relid); -static void stop_decoding_worker(void); + +static void start_repack_decoding_worker(Oid relid); +static void stop_repack_decoding_worker(void); static void repack_worker_internal(dsm_segment *seg); static void export_initial_snapshot(Snapshot snapshot, DecodingWorkerShared *shared); static Snapshot get_initial_snapshot(DecodingWorker *worker); +extern bool am_decoding_for_repack(void); +static void DecodingWorkerFileName(char *fname, Oid relid, uint32 seq); + static void ProcessRepackMessage(StringInfo msg); static const char *RepackCommandAsString(RepackCommand cmd); @@ -369,17 +369,8 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) parser_errposition(pstate, opt->location)); } - /* - * Determine the lock mode expected by cluster_rel(). - * - * In the exclusive case, we obtain AccessExclusiveLock right away to - * avoid lock-upgrade hazard in the single-transaction case. In the - * CONCURRENTLY case, the AccessExclusiveLock will only be used at the end - * of processing, supposedly for very short time. Until then, we'll have - * to unlock the relation temporarily, so there's no lock-upgrade hazard. - */ - lockmode = (params.options & CLUOPT_CONCURRENT) == 0 ? - AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lockmode = RepackLockLevel((params.options & CLUOPT_CONCURRENT) != 0); /* * If a single relation is specified, process it and we're done ... unless @@ -434,6 +425,12 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) "Repack", ALLOCSET_DEFAULT_SIZES); + /* + * Since we open a new transaction for each relation, we have to check + * that the relation still is what we think it is. + * + * In single-transaction CLUSTER, we don't need the overhead. + */ params.options |= CLUOPT_RECHECK; /* @@ -544,6 +541,22 @@ ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel) MemoryContextDelete(repack_context); } +/* + * In the non-concurrent case, we obtain AccessExclusiveLock throughout the + * operation to avoid any lock-upgrade hazards. In the concurrent case, we + * grab ShareUpdateExclusiveLock (jsut like VACUUM) for most of the + * processing and only acquire AccessExclusiveLock at the end, to swap the + * relation -- supposedly for a short time. + */ +static LOCKMODE +RepackLockLevel(bool concurrent) +{ + if (concurrent) + return ShareUpdateExclusiveLock; + else + return AccessExclusiveLock; +} + /* * cluster_rel * @@ -583,25 +596,22 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, bool concurrent = ((params->options & CLUOPT_CONCURRENT) != 0); Oid ident_idx = InvalidOid; - /* - * The lock mode is AccessExclusiveLock for normal processing and - * ShareUpdateExclusiveLock for concurrent processing (so that SELECT, - * INSERT, UPDATE and DELETE commands work, but cluster_rel() cannot be - * called concurrently for the same relation). - */ - lmode = !concurrent ? AccessExclusiveLock : ShareUpdateExclusiveLock; + /* Determine the lock mode to use. */ + lmode = RepackLockLevel(concurrent); - /* There are specific requirements on concurrent processing. */ + /* + * Check some preconditions in the concurrent case. This also obtains the + * replica index OID. + */ if (concurrent) { /* - * Make sure we have no XID assigned, otherwise call of - * repack_setup_logical_decoding() can cause a deadlock. + * Make sure we're not in a transaction block. * - * The existence of transaction block actually does not imply that XID - * was already assigned, but it very likely is. We might want to check - * the result of GetCurrentTransactionIdIfAny() instead, but that - * would be less clear from user's perspective. + * The reason is that repack_setup_logical_decoding() could deadlock + * if there's an XID already assigned. It would be possible to run in + * a transaction block if we had no XID, but this restriction is + * simpler for users to understand and we don't lose anything. */ PreventInTransactionBlock(isTopLevel, "REPACK (CONCURRENTLY)"); @@ -626,15 +636,11 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, RestrictSearchPath(); /* - * Since we may open a new transaction for each relation, we have to check - * that the relation still is what we think it is. + * Recheck that the relation is still what it was when we started. * - * If this is a single-transaction CLUSTER, we can skip these tests. We - * *must* skip the one on indisclustered since it would reject an attempt - * to cluster a not-previously-clustered index. - * - * XXX move [some of] these comments to where the RECHECK flag is - * determined? + * Note that it's critical to skip this in single-relation CLUSTER; + * otherwise, we would reject an attempt to cluster using a + * not-previously-clustered index. */ if (recheck && !cluster_rel_recheck(cmd, OldHeap, indexOid, save_userid, @@ -754,7 +760,7 @@ cluster_rel(RepackCommand cmd, Relation OldHeap, Oid indexOid, * However it still seems a good practice to make sure that the * worker never survives the REPACK command. */ - stop_decoding_worker(); + stop_repack_decoding_worker(); } } PG_END_TRY(); @@ -1093,7 +1099,7 @@ rebuild_relation(Relation OldHeap, Relation index, bool verbose, * clustering index) and checking again if it's still eligible for * REPACK CONCURRENTLY. */ - start_decoding_worker(tableOid); + start_repack_decoding_worker(tableOid); /* * Wait until the worker has the initial snapshot and retrieve it. @@ -2538,7 +2544,6 @@ RepackCommandAsString(RepackCommand cmd) return "???"; /* keep compiler quiet */ } - /* * Is this backend performing logical decoding on behalf of REPACK * (CONCURRENTLY) ? @@ -3688,7 +3693,7 @@ build_new_indexes(Relation NewHeap, Relation OldHeap, List *OldIndexes) * contents to a new table. */ static void -start_decoding_worker(Oid relid) +start_repack_decoding_worker(Oid relid) { Size size; dsm_segment *seg; @@ -3779,7 +3784,7 @@ start_decoding_worker(Oid relid) * we need to stop it explicitly at least on ERROR in the launching backend. */ static void -stop_decoding_worker(void) +stop_repack_decoding_worker(void) { BgwHandleStatus status; @@ -3817,12 +3822,6 @@ stop_decoding_worker(void) decoding_worker = NULL; } -/* Is this process a REPACK worker? */ -static bool is_repack_worker = false; - -static pid_t backend_pid; -static ProcNumber backend_proc_number; - /* * See ParallelWorkerShutdown for details. */ @@ -3869,7 +3868,7 @@ RepackWorkerMain(Datum main_arg) /* * Join locking group - see the comments around the call of - * start_decoding_worker(). + * start_repack_decoding_worker(). */ if (!BecomeLockGroupMember(shared->backend_proc, backend_pid)) /* The leader is not running anymore. */ @@ -4039,6 +4038,18 @@ get_initial_snapshot(DecodingWorker *worker) return snapshot; } +/* + * Generate worker's output file name. If relations of the same 'relid' happen + * to be processed at the same time, they must be from different databases and + * therefore different backends must be involved. (PID is already present in + * the fileset name.) + */ +static void +DecodingWorkerFileName(char *fname, Oid relid, uint32 seq) +{ + snprintf(fname, MAXPGPATH, "%u-%u", relid, seq); +} + bool IsRepackWorker(void) { @@ -4067,7 +4078,6 @@ void ProcessRepackMessages(void) { MemoryContext oldcontext; - static MemoryContext hpm_context = NULL; /* diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f8a8d1681e9..9e876d55e27 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/parallel.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "libpq/pqsignal.h" #include "miscadmin.h" #include "pgstat.h" diff --git a/src/backend/replication/pgoutput_repack/pgoutput_repack.c b/src/backend/replication/pgoutput_repack/pgoutput_repack.c index 032fbd0e5b0..cc9ce615b18 100644 --- a/src/backend/replication/pgoutput_repack/pgoutput_repack.c +++ b/src/backend/replication/pgoutput_repack/pgoutput_repack.c @@ -13,7 +13,7 @@ #include "postgres.h" #include "access/detoast.h" -#include "commands/cluster.h" +#include "commands/repack_internal.h" #include "replication/snapbuild.h" #include "utils/memutils.h" @@ -176,7 +176,7 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, ConcurrentChangeKind kind, HeapTuple tuple) { RepackDecodingState *dstate; - MemoryContext oldcxt; + MemoryContext oldcxt; BufFile *file; List *attrs_ext = NIL; int natt_ext; @@ -226,7 +226,10 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, slot_getsomeattrs(slot, i + 1); - /* This is a non-null varlena datum, but we only care if it's out-of-line */ + /* + * This is a non-null varlena datum, but we only care if it's + * out-of-line + */ varlen = (varlena *) DatumGetPointer(slot->tts_values[i]); if (!VARATT_IS_EXTERNAL(varlen)) continue; @@ -244,8 +247,8 @@ repack_store_change(LogicalDecodingContext *ctx, Relation relation, * attributes (those actually should never appear on disk), so * only TOASTed attribute can be seen here. * - * FIXME in what circumstances can an ONDISK attr appear? - * Why aren't these written separately? + * FIXME in what circumstances can an ONDISK attr appear? Why + * aren't these written separately? */ Assert(VARATT_IS_EXTERNAL_ONDISK(varlen)); } diff --git a/src/include/commands/cluster.h b/src/include/commands/cluster.h index 1c0ac3ab4f5..1528d34fa42 100644 --- a/src/include/commands/cluster.h +++ b/src/include/commands/cluster.h @@ -13,17 +13,12 @@ #ifndef CLUSTER_H #define CLUSTER_H -#include "nodes/execnodes.h" +#include <signal.h> + #include "nodes/parsenodes.h" #include "parser/parse_node.h" -#include "replication/decode.h" -#include "postmaster/bgworker.h" -#include "replication/logical.h" -#include "storage/buffile.h" #include "storage/lockdefs.h" -#include "storage/shm_mq.h" #include "utils/relcache.h" -#include "utils/resowner.h" /* flag bits for ClusterParams->options */ @@ -34,55 +29,14 @@ #define CLUOPT_ANALYZE 0x08 /* do an ANALYZE */ #define CLUOPT_CONCURRENT 0x10 /* allow concurrent data changes */ - /* options for CLUSTER */ typedef struct ClusterParams { bits32 options; /* bitmask of CLUOPT_* */ } ClusterParams; - -/* - * The following definitions are used by REPACK CONCURRENTLY. - */ - -/* - * Stored as a single byte in the output file. - */ -#define CHANGE_INSERT 'i' -#define CHANGE_UPDATE_OLD 'u' -#define CHANGE_UPDATE_NEW 'U' -#define CHANGE_DELETE 'd' -typedef char ConcurrentChangeKind; - -/* - * Logical decoding state. - * - * The output plugin uses it to store the data changes that it decodes from - * WAL while the table contents is being copied to a new storage. - */ -typedef struct RepackDecodingState -{ -#ifdef USE_ASSERT_CHECKING - /* The relation whose changes we're decoding. */ - Oid relid; -#endif - - /* Per-change memory context. */ - MemoryContext change_cxt; - - /* A tuple slot used to pass tuples back and forth */ - TupleTableSlot *slot; - - /* The current output file. */ - BufFile *file; -} RepackDecodingState; - extern PGDLLIMPORT volatile sig_atomic_t RepackMessagePending; -extern bool IsRepackWorker(void); -extern void HandleRepackMessageInterrupt(void); -extern void ProcessRepackMessages(void); extern void ExecRepack(ParseState *pstate, RepackStmt *stmt, bool isTopLevel); @@ -104,8 +58,9 @@ extern void finish_heap_swap(Oid OIDOldHeap, Oid OIDNewHeap, MultiXactId cutoffMulti, char newrelpersistence); -extern bool am_decoding_for_repack(void); -extern bool change_useless_for_repack(XLogRecordBuffer *buf); +extern bool IsRepackWorker(void); +extern void HandleRepackMessageInterrupt(void); +extern void ProcessRepackMessages(void); + -extern void RepackWorkerMain(Datum main_arg); #endif /* CLUSTER_H */ diff --git a/src/include/commands/repack_internal.h b/src/include/commands/repack_internal.h new file mode 100644 index 00000000000..f90c973f5a0 --- /dev/null +++ b/src/include/commands/repack_internal.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * repack_internal.h + * header for REPACK internals + * + * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group + * Portions Copyright (c) 1994-5, Regents of the University of California + * + * src/include/commands/repack_internal.h + * + *------------------------------------------------------------------------- + */ +#ifndef REPACK_INTERNAL_H +#define REPACK_INTERNAL_H + +#include "nodes/execnodes.h" +#include "replication/decode.h" +#include "postmaster/bgworker.h" +#include "replication/logical.h" +#include "storage/buffile.h" +#include "storage/shm_mq.h" +#include "utils/resowner.h" + +/* + * Stored as a single byte in the output file. + */ +#define CHANGE_INSERT 'i' +#define CHANGE_UPDATE_OLD 'u' +#define CHANGE_UPDATE_NEW 'U' +#define CHANGE_DELETE 'd' +typedef char ConcurrentChangeKind; + +/* + * Logical decoding state. + * + * The output plugin uses it to store the data changes that it decodes from + * WAL while the table contents is being copied to a new storage. + */ +typedef struct RepackDecodingState +{ +#ifdef USE_ASSERT_CHECKING + /* The relation whose changes we're decoding. */ + Oid relid; +#endif + + /* Per-change memory context. */ + MemoryContext change_cxt; + + /* A tuple slot used to pass tuples back and forth */ + TupleTableSlot *slot; + + /* The current output file. */ + BufFile *file; +} RepackDecodingState; + + +extern void RepackWorkerMain(Datum main_arg); + +#endif /* REPACK_INTERNAL_H */ diff --git a/src/include/replication/decode.h b/src/include/replication/decode.h index 49f00fc48b8..02b5393474c 100644 --- a/src/include/replication/decode.h +++ b/src/include/replication/decode.h @@ -31,4 +31,8 @@ extern void logicalmsg_decode(LogicalDecodingContext *ctx, XLogRecordBuffer *buf extern void LogicalDecodingProcessRecord(LogicalDecodingContext *ctx, XLogReaderState *record); +/* in commands/cluster.c */ +extern bool change_useless_for_repack(XLogRecordBuffer *buf); + + #endif -- 2.47.3 --gwom7bl7ogtszo4k Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="v44-0008-Use-BulkInsertState-when-copying-data-to-the-new.patch" ^ permalink raw reply [nested|flat] 354+ messages in thread
* [PATCH v11a 2/2] ci: Remove support for cirrus-ci based CI @ 2026-06-04 13:34 Andres Freund <andres@anarazel.de> 0 siblings, 0 replies; 354+ messages in thread From: Andres Freund @ 2026-06-04 13:34 UTC (permalink / raw) As mentioned in the earlier commit, cirrus-ci has shut down. Therefore remove all files related to running CI via cirrus. Also update comments / code that were referencing cirrus-ci. Discussion: https://postgr.es/m/3ydjipcr7kbss57nvi67noplncqhesl5eyb6wgol4ccjxynspv%40yatlykpribmm --- src/bin/pg_combinebackup/t/010_hardlink.pl | 12 +- .cirrus.yml | 91 -- src/test/perl/PostgreSQL/Test/Cluster.pm | 5 +- .cirrus.star | 143 --- .cirrus.tasks.yml | 1022 -------------------- src/tools/ci/ci_macports_packages.sh | 7 +- src/tools/ci/gcp_ram_disk.sh | 27 - 7 files changed, 11 insertions(+), 1296 deletions(-) delete mode 100644 .cirrus.yml delete mode 100644 .cirrus.star delete mode 100644 .cirrus.tasks.yml delete mode 100755 src/tools/ci/gcp_ram_disk.sh diff --git a/src/bin/pg_combinebackup/t/010_hardlink.pl b/src/bin/pg_combinebackup/t/010_hardlink.pl index b6e8a9128af..5fbbe6a923b 100644 --- a/src/bin/pg_combinebackup/t/010_hardlink.pl +++ b/src/bin/pg_combinebackup/t/010_hardlink.pl @@ -18,13 +18,13 @@ $primary->append_conf('postgresql.conf', 'autovacuum = off'); $primary->start; # Create a couple of tables (~264KB each). -# Note: Cirrus CI runs some tests with a very small segment size, so, in that +# Note: CI runs some tests with a very small segment size, so, in that # environment, a single table of 264KB would have both a segment with a link -# count of 1 and also one with a link count of 2. But in a normal installation, -# segment size is 1GB. Therefore, we use 2 different tables here: for test_1, -# all segments (or the only one) will have two hard links; for test_2, the -# last segment (or the only one) will have 1 hard link, and any others will -# have 2. +# count of 1 and also one with a link count of 2. But in a normal +# installation, segment size is 1GB. Therefore, we use 2 different tables +# here: for test_1, all segments (or the only one) will have two hard links; +# for test_2, the last segment (or the only one) will have 1 hard link, and +# any others will have 2. my $query = <<'EOM'; CREATE TABLE test_%s AS SELECT x.id::bigint, diff --git a/.cirrus.yml b/.cirrus.yml deleted file mode 100644 index 3f75852e84e..00000000000 --- a/.cirrus.yml +++ /dev/null @@ -1,91 +0,0 @@ -# CI configuration file for CI utilizing cirrus-ci.org -# -# For instructions on how to enable the CI integration in a repository and -# further details, see src/tools/ci/README -# -# -# The actual CI tasks are defined in .cirrus.tasks.yml. To make the compute -# resources for CI configurable on a repository level, the "final" CI -# configuration is the combination of: -# -# 1) the contents of this file -# -# 2) computed environment variables -# -# Used to enable/disable tasks based on the execution environment. See -# .cirrus.star: compute_environment_vars() -# -# 3) if defined, the contents of the file referenced by the, repository -# level, REPO_CI_CONFIG_GIT_URL variable (see -# https://cirrus-ci.org/guide/programming-tasks/#fs for the accepted -# format) -# -# This allows running tasks in a different execution environment than the -# default, e.g. to have sufficient resources for cfbot. -# -# 4) .cirrus.tasks.yml -# -# This composition is done by .cirrus.star - - -env: - # Source of images / containers - GCP_PROJECT: pg-ci-images - IMAGE_PROJECT: $GCP_PROJECT - CONTAINER_REPO: us-docker.pkg.dev/${GCP_PROJECT}/ci - DISK_SIZE: 25 - - -# Define how to run various types of tasks. - -# VMs provided by cirrus-ci. Each user has a limited number of "free" credits -# for testing. -cirrus_community_vm_template: &cirrus_community_vm_template - compute_engine_instance: - image_project: $IMAGE_PROJECT - image: family/$IMAGE_FAMILY - platform: $PLATFORM - cpu: $CPUS - disk: $DISK_SIZE - - -default_linux_task_template: &linux_task_template - env: - PLATFORM: linux - <<: *cirrus_community_vm_template - - -default_freebsd_task_template: &freebsd_task_template - env: - PLATFORM: freebsd - <<: *cirrus_community_vm_template - -default_netbsd_task_template: &netbsd_task_template - env: - PLATFORM: netbsd - <<: *cirrus_community_vm_template - -default_openbsd_task_template: &openbsd_task_template - env: - PLATFORM: openbsd - <<: *cirrus_community_vm_template - - -default_windows_task_template: &windows_task_template - env: - PLATFORM: windows - <<: *cirrus_community_vm_template - - -# macos workers provided by cirrus-ci -default_macos_task_template: &macos_task_template - env: - PLATFORM: macos - macos_instance: - image: $IMAGE - - -# Contents of REPO_CI_CONFIG_GIT_URL, if defined, will be inserted here, -# followed by the contents .cirrus.tasks.yml. This allows -# REPO_CI_CONFIG_GIT_URL to override how the task types above will be -# executed, e.g. using a custom compute account or permanent workers. diff --git a/src/test/perl/PostgreSQL/Test/Cluster.pm b/src/test/perl/PostgreSQL/Test/Cluster.pm index 4fcb1f6be56..529f49efee1 100644 --- a/src/test/perl/PostgreSQL/Test/Cluster.pm +++ b/src/test/perl/PostgreSQL/Test/Cluster.pm @@ -363,9 +363,8 @@ This tries to connect to the server, to test whether it works or not,, so the server is up and running. Otherwise this can return 0 even if there's nothing wrong with raw_connect() itself. -Notably, raw_connect() does not work on Unix domain sockets on -Strawberry perl 5.26.3.1 on Windows, which we use in Cirrus CI images -as of this writing. It dies with "not implemented on this +Notably, raw_connect() does not work on Unix domain sockets on at least +Strawberry perl 5.26.3.1 on Windows. It dies with "not implemented on this architecture". =cut diff --git a/.cirrus.star b/.cirrus.star deleted file mode 100644 index e9bb672b959..00000000000 --- a/.cirrus.star +++ /dev/null @@ -1,143 +0,0 @@ -"""Additional CI configuration, using the starlark language. See -https://cirrus-ci.org/guide/programming-tasks/#introduction-into-starlark - -See also the starlark specification at -https://github.com/bazelbuild/starlark/blob/master/spec.md - -See also .cirrus.yml and src/tools/ci/README -""" - -load("cirrus", "env", "fs", "re", "yaml") - - -def main(): - """The main function is executed by cirrus-ci after loading .cirrus.yml and can - extend the CI definition further. - - As documented in .cirrus.yml, the final CI configuration is composed of - - 1) the contents of .cirrus.yml - - 2) computed environment variables - - 3) if defined, the contents of the file referenced by the, repository - level, REPO_CI_CONFIG_GIT_URL variable (see - https://cirrus-ci.org/guide/programming-tasks/#fs for the accepted - format) - - 4) .cirrus.tasks.yml - """ - - output = "" - - # 1) is evaluated implicitly - - - # Add 2) - additional_env = compute_environment_vars() - env_fmt = """ -### -# Computed environment variables start here -### -{0} -### -# Computed environment variables end here -### -""" - output += env_fmt.format(yaml.dumps({'env': additional_env})) - - - # Add 3) - repo_config_url = env.get("REPO_CI_CONFIG_GIT_URL") - if repo_config_url != None: - print("loading additional configuration from \"{}\"".format(repo_config_url)) - output += config_from(repo_config_url) - else: - output += "\n# REPO_CI_CONFIG_URL was not set\n" - - - # Add 4) - output += config_from(".cirrus.tasks.yml") - - - return output - - -def compute_environment_vars(): - cenv = {} - - ### - # Some tasks are manually triggered by default because they might use too - # many resources for users of free Cirrus credits, but they can be - # triggered automatically by naming them in an environment variable e.g. - # REPO_CI_AUTOMATIC_TRIGGER_TASKS="task_name other_task" under "Repository - # Settings" on Cirrus CI's website. - - default_manual_trigger_tasks = ['mingw', 'netbsd', 'openbsd'] - - repo_ci_automatic_trigger_tasks = env.get('REPO_CI_AUTOMATIC_TRIGGER_TASKS', '') - for task in default_manual_trigger_tasks: - name = 'CI_TRIGGER_TYPE_' + task.upper() - if repo_ci_automatic_trigger_tasks.find(task) != -1: - value = 'automatic' - else: - value = 'manual' - cenv[name] = value - ### - - ### - # Parse "ci-os-only:" tag in commit message and set - # CI_{$OS}_ENABLED variable for each OS - - # We want to disable SanityCheck if testing just a specific OS. This - # shortens push-wait-for-ci cycle time a bit when debugging operating - # system specific failures. Just treating it as an OS in that case - # suffices. - - operating_systems = [ - 'compilerwarnings', - 'freebsd', - 'linux', - 'macos', - 'mingw', - 'netbsd', - 'openbsd', - 'sanitycheck', - 'windows', - ] - commit_message = env.get('CIRRUS_CHANGE_MESSAGE') - match_re = r"(^|.*\n)ci-os-only: ([^\n]+)($|\n.*)" - - # re.match() returns an array with a tuple of (matched-string, match_1, ...) - m = re.match(match_re, commit_message) - if m and len(m) > 0: - os_only = m[0][2] - os_only_list = re.split(r'[, ]+', os_only) - else: - os_only_list = operating_systems - - for os in operating_systems: - os_enabled = os in os_only_list - cenv['CI_{0}_ENABLED'.format(os.upper())] = os_enabled - ### - - return cenv - - -def config_from(config_src): - """return contents of config file `config_src`, surrounded by markers - indicating start / end of the included file - """ - - config_contents = fs.read(config_src) - config_fmt = """ - -### -# contents of config file `{0}` start here -### -{1} -### -# contents of config file `{0}` end here -### -""" - return config_fmt.format(config_src, config_contents) diff --git a/.cirrus.tasks.yml b/.cirrus.tasks.yml deleted file mode 100644 index 8683d1ae9c7..00000000000 --- a/.cirrus.tasks.yml +++ /dev/null @@ -1,1022 +0,0 @@ -# CI configuration file for CI utilizing cirrus-ci.org -# -# For instructions on how to enable the CI integration in a repository and -# further details, see src/tools/ci/README -# -# -# NB: Different tasks intentionally test with different, non-default, -# configurations, to increase the chance of catching problems. Each task with -# non-obvious non-default documents their oddity at the top of the task, -# prefixed by "SPECIAL:". - - -env: - # The lower depth accelerates git clone. Use a bit of depth so that - # concurrent tasks and retrying older jobs have a chance of working. - CIRRUS_CLONE_DEPTH: 500 - # Useful to be able to analyse what in a script takes long - CIRRUS_LOG_TIMESTAMP: true - - CCACHE_MAXSIZE: "250M" - - # target to test, for all but windows - CHECK: check-world PROVE_FLAGS=$PROVE_FLAGS - CHECKFLAGS: -Otarget - PROVE_FLAGS: --timer - # Build test dependencies as part of the build step, to see compiler - # errors/warnings in one place. - MBUILD_TARGET: all testprep - MTEST_ARGS: --print-errorlogs --no-rebuild -C build - PGCTLTIMEOUT: 120 # avoids spurious failures during parallel tests - TEMP_CONFIG: ${CIRRUS_WORKING_DIR}/src/tools/ci/pg_ci_base.conf - PG_TEST_EXTRA: kerberos ldap ssl libpq_encryption load_balance oauth - - # Postgres config args for the meson builds, shared between all meson tasks - # except the 'SanityCheck' task - MESON_COMMON_PG_CONFIG_ARGS: -Dcassert=true -Dinjection_points=true - - # Meson feature flags shared by all meson tasks, except: - # SanityCheck: uses almost no dependencies. - # Windows - VS: has fewer dependencies than listed here, so defines its own. - # Linux: uses the 'auto' feature option to test meson feature autodetection. - MESON_COMMON_FEATURES: >- - -Dauto_features=disabled - -Dldap=enabled - -Dssl=openssl - -Dtap_tests=enabled - -Dplperl=enabled - -Dplpython=enabled - -Ddocs=enabled - -Dicu=enabled - -Dlibxml=enabled - -Dlibxslt=enabled - -Dlz4=enabled - -Dpltcl=enabled - -Dreadline=enabled - -Dzlib=enabled - -Dzstd=enabled - - -# What files to preserve in case tests fail -on_failure_ac: &on_failure_ac - log_artifacts: - paths: - - "**/*.log" - - "**/*.diffs" - - "**/regress_log_*" - type: text/plain - -on_failure_meson: &on_failure_meson - testrun_artifacts: - paths: - - "build*/testrun/**/*.log" - - "build*/testrun/**/*.diffs" - - "build*/testrun/**/regress_log_*" - type: text/plain - - # In theory it'd be nice to upload the junit files meson generates, so that - # cirrus will nicely annotate the commit. Unfortunately the files don't - # contain identifiable file + line numbers right now, so the annotations - # don't end up useful. We could probably improve on that with a some custom - # conversion script, but ... - meson_log_artifacts: - path: "build*/meson-logs/*.txt" - type: text/plain - - -# To avoid unnecessarily spinning up a lot of VMs / containers for entirely -# broken commits, have a minimal task that all others depend on. -# -# SPECIAL: -# - Builds with --auto-features=disabled and thus almost no enabled -# dependencies -task: - name: SanityCheck - - # If a specific OS is requested, don't run the sanity check. This shortens - # push-wait-for-ci cycle time a bit when debugging operating system specific - # failures. Uses skip instead of only_if, as cirrus otherwise warns about - # only_if conditions not matching. - skip: $CI_SANITYCHECK_ENABLED == false - - env: - CPUS: 4 - BUILD_JOBS: 8 - TEST_JOBS: 8 - IMAGE_FAMILY: pg-ci-trixie - CCACHE_DIR: ${CIRRUS_WORKING_DIR}/ccache_dir - # no options enabled, should be small - CCACHE_MAXSIZE: "150M" - - # While containers would start up a bit quicker, building is a bit - # slower. This way we don't have to maintain a container image. - <<: *linux_task_template - - ccache_cache: - folder: $CCACHE_DIR - - create_user_script: | - useradd -m postgres - chown -R postgres:postgres . - mkdir -p ${CCACHE_DIR} - chown -R postgres:postgres ${CCACHE_DIR} - echo '* - memlock 134217728' > /etc/security/limits.d/postgres.conf - su postgres -c "ulimit -l -H && ulimit -l -S" - # Can't change container's kernel.core_pattern. Postgres user can't write - # to / normally. Change that. - chown root:postgres / - chmod g+rwx / - - configure_script: | - su postgres <<-EOF - set -e - meson setup \ - --buildtype=debug \ - --auto-features=disabled \ - -Ddefault_library=shared \ - -Dtap_tests=enabled \ - build - EOF - build_script: | - su postgres <<-EOF - set -e - ninja -C build -j${BUILD_JOBS} ${MBUILD_TARGET} - EOF - upload_caches: ccache - - # Run a minimal set of tests. The main regression tests take too long for - # this purpose. For now this is a random quick pg_regress style test, and a - # tap test that exercises both a frontend binary and the backend. - test_minimal_script: | - su postgres <<-EOF - set -e - ulimit -c unlimited - meson test $MTEST_ARGS --suite setup - meson test $MTEST_ARGS --num-processes ${TEST_JOBS} \ - cube/regress pg_ctl/001_start_stop - EOF - - on_failure: - <<: *on_failure_meson - cores_script: | - mkdir -m 770 /tmp/cores - find / -maxdepth 1 -type f -name 'core*' -exec mv '{}' /tmp/cores/ \; - src/tools/ci/cores_backtrace.sh linux /tmp/cores - - -# SPECIAL: -# - Uses postgres specific CPPFLAGS that increase test coverage -# - Specifies configuration options that test reading/writing/copying of node trees -# - Specifies debug_parallel_query=regress, to catch related issues during CI -# - Also runs tests against a running postgres instance, see test_running_script -task: - name: FreeBSD - Meson - - env: - CPUS: 4 - BUILD_JOBS: 4 - TEST_JOBS: 8 - IMAGE_FAMILY: pg-ci-freebsd - DISK_SIZE: 50 - - CCACHE_DIR: /tmp/ccache_dir - CPPFLAGS: -DRELCACHE_FORCE_RELEASE -DENFORCE_REGRESSION_TEST_NAME_RESTRICTIONS - CFLAGS: -Og -ggdb - - # Several buildfarm animals enable these options. Without testing them - # during CI, it would be easy to cause breakage on the buildfarm with CI - # passing. - PG_TEST_INITDB_EXTRA_OPTS: >- - -c debug_copy_parse_plan_trees=on - -c debug_write_read_parse_plan_trees=on - -c debug_raw_expression_coverage_test=on - -c debug_parallel_query=regress - PG_TEST_PG_UPGRADE_MODE: --link - - MESON_FEATURES: >- - -Ddtrace=enabled - -Dgssapi=enabled - -Dlibcurl=enabled - -Dnls=enabled - -Dpam=enabled - -Dtcl_version=tcl86 - -Duuid=bsd - - <<: *freebsd_task_template - - depends_on: SanityCheck - only_if: $CI_FREEBSD_ENABLED - - sysinfo_script: | - id - uname -a - ulimit -a -H && ulimit -a -S - export - - ccache_cache: - folder: $CCACHE_DIR - setup_ram_disk_script: src/tools/ci/gcp_ram_disk.sh - create_user_script: | - pw useradd postgres - chown -R postgres:postgres . - mkdir -p ${CCACHE_DIR} - chown -R postgres:postgres ${CCACHE_DIR} - setup_core_files_script: | - mkdir -m 770 /tmp/cores - chown root:postgres /tmp/cores - sysctl kern.corefile='/tmp/cores/%N.%P.core' - setup_additional_packages_script: | - #pkg install -y ... - - # NB: Intentionally build without -Dllvm. The freebsd image size is already - # large enough to make VM startup slow, and even without llvm freebsd - # already takes longer than other platforms except for windows. - configure_script: | - su postgres <<-EOF - set -e - meson setup \ - ${MESON_COMMON_PG_CONFIG_ARGS} \ - --buildtype=debug \ - -Dextra_lib_dirs=/usr/local/lib -Dextra_include_dirs=/usr/local/include/ \ - ${MESON_COMMON_FEATURES} ${MESON_FEATURES} \ - build - EOF - build_script: su postgres -c 'ninja -C build -j${BUILD_JOBS} ${MBUILD_TARGET}' - upload_caches: ccache - - test_world_script: | - su postgres <<-EOF - set -e - ulimit -c unlimited - meson test $MTEST_ARGS --num-processes ${TEST_JOBS} - EOF - - # test runningcheck, freebsd chosen because it's currently fast enough - test_running_script: | - su postgres <<-EOF - set -e - ulimit -c unlimited - meson test $MTEST_ARGS --quiet --suite setup - export LD_LIBRARY_PATH="$(pwd)/build/tmp_install/usr/local/pgsql/lib/:$LD_LIBRARY_PATH" - mkdir -p build/testrun - build/tmp_install/usr/local/pgsql/bin/initdb -N build/runningcheck --no-instructions -A trust - echo "include '$(pwd)/src/tools/ci/pg_ci_base.conf'" >> build/runningcheck/postgresql.conf - build/tmp_install/usr/local/pgsql/bin/pg_ctl -c -o '-c fsync=off' -D build/runningcheck -l build/testrun/runningcheck.log start - meson test $MTEST_ARGS --num-processes ${TEST_JOBS} --setup running - build/tmp_install/usr/local/pgsql/bin/pg_ctl -D build/runningcheck stop - EOF - - on_failure: - # if the server continues running, it often causes cirrus-ci to fail - # during upload, as it doesn't expect artifacts to change size - stop_running_script: | - su postgres <<-EOF - set -e - build/tmp_install/usr/local/pgsql/bin/pg_ctl -D build/runningcheck stop || true - EOF - <<: *on_failure_meson - cores_script: src/tools/ci/cores_backtrace.sh freebsd /tmp/cores - - -task: - depends_on: SanityCheck - - env: - # Below are experimentally derived to be a decent choice. - CPUS: 4 - BUILD_JOBS: 8 - TEST_JOBS: 8 - - # Default working directory is /tmp, but its total size (1.2 GB) is not - # enough, so different working and cache directory are set. - CIRRUS_WORKING_DIR: /home/postgres/postgres - CCACHE_DIR: /home/postgres/cache - - PATH: /usr/sbin:$PATH - CORE_DUMP_DIR: /var/crash - - matrix: - - name: NetBSD - Meson - # See REPO_CI_AUTOMATIC_TRIGGER_TASKS in .cirrus.star - trigger_type: $CI_TRIGGER_TYPE_NETBSD - only_if: $CI_NETBSD_ENABLED - env: - OS_NAME: netbsd - IMAGE_FAMILY: pg-ci-netbsd-postgres - PKGCONFIG_PATH: '/usr/lib/pkgconfig:/usr/pkg/lib/pkgconfig' - # initdb fails with: 'invalid locale settings' error on NetBSD. - # Force 'LANG' and 'LC_*' variables to be 'C'. - # See https://postgr.es/m/2490325.1734471752%40sss.pgh.pa.us - LANG: "C" - LC_ALL: "C" - # -Duuid is not set for the NetBSD, see the comment below, above - # configure_script, for more information. - MESON_FEATURES: >- - -Dgssapi=enabled - -Dlibcurl=enabled - -Dnls=enabled - -Dpam=enabled - - setup_additional_packages_script: | - #pkgin -y install ... - <<: *netbsd_task_template - - - name: OpenBSD - Meson - # See REPO_CI_AUTOMATIC_TRIGGER_TASKS in .cirrus.star - trigger_type: $CI_TRIGGER_TYPE_OPENBSD - only_if: $CI_OPENBSD_ENABLED - env: - OS_NAME: openbsd - IMAGE_FAMILY: pg-ci-openbsd-postgres - PKGCONFIG_PATH: '/usr/lib/pkgconfig:/usr/local/lib/pkgconfig' - CORE_DUMP_EXECUTABLE_DIR: $CIRRUS_WORKING_DIR/build/tmp_install/usr/local/pgsql/bin - - MESON_FEATURES: >- - -Dbsd_auth=enabled - -Dlibcurl=enabled - -Dtcl_version=tcl86 - -Duuid=e2fs - - setup_additional_packages_script: | - #pkg_add -I ... - # Always core dump to ${CORE_DUMP_DIR} - set_core_dump_script: sysctl -w kern.nosuidcoredump=2 - <<: *openbsd_task_template - - sysinfo_script: | - locale - id - uname -a - ulimit -a -H && ulimit -a -S - env - - ccache_cache: - folder: $CCACHE_DIR - setup_ram_disk_script: src/tools/ci/gcp_ram_disk.sh - create_user_script: | - useradd postgres - chown -R postgres:users /home/postgres - mkdir -p ${CCACHE_DIR} - chown -R postgres:users ${CCACHE_DIR} - setup_core_files_script: | - mkdir -p ${CORE_DUMP_DIR} - chmod -R 770 ${CORE_DUMP_DIR} - chown -R postgres:users ${CORE_DUMP_DIR} - - # -Duuid=bsd is not set since 'bsd' uuid option - # is not working on NetBSD & OpenBSD. See - # https://www.postgresql.org/message-id/17358-89806e7420797025@postgresql.org - # And other uuid options are not available on NetBSD. - configure_script: | - su postgres <<-EOF - set -e - meson setup \ - ${MESON_COMMON_PG_CONFIG_ARGS} \ - --buildtype=debugoptimized \ - --pkg-config-path ${PKGCONFIG_PATH} \ - ${MESON_COMMON_FEATURES} ${MESON_FEATURES} \ - build - EOF - - build_script: su postgres -c 'ninja -C build -j${BUILD_JOBS} ${MBUILD_TARGET}' - upload_caches: ccache - - test_world_script: | - su postgres <<-EOF - set -e - ulimit -c unlimited - meson test $MTEST_ARGS --num-processes ${TEST_JOBS} - EOF - - on_failure: - <<: *on_failure_meson - cores_script: | - # Although we try to configure the OS to core dump inside - # ${CORE_DUMP_DIR}, they may not obey this. So, move core files to the - # ${CORE_DUMP_DIR} directory. - find build/ -type f -name '*.core' -exec mv '{}' ${CORE_DUMP_DIR} \; - src/tools/ci/cores_backtrace.sh ${OS_NAME} ${CORE_DUMP_DIR} ${CORE_DUMP_EXECUTABLE_DIR} - - -# configure feature flags, shared between the task running the linux tests and -# the CompilerWarnings task -LINUX_CONFIGURE_FEATURES: &LINUX_CONFIGURE_FEATURES >- - --with-gssapi - --with-icu - --with-ldap - --with-libcurl - --with-libxml - --with-libxslt - --with-llvm - --with-lz4 - --with-pam - --with-perl - --with-python - --with-selinux - --with-ssl=openssl - --with-systemd - --with-tcl --with-tclconfig=/usr/lib/tcl8.6/ - --with-uuid=ossp - --with-zstd - - -# Check SPECIAL in the matrix: below -task: - env: - CPUS: 4 - BUILD_JOBS: 4 - TEST_JOBS: 8 # experimentally derived to be a decent choice - IMAGE_FAMILY: pg-ci-trixie - - CCACHE_DIR: /tmp/ccache_dir - DEBUGINFOD_URLS: "https://debuginfod.debian.net"; - - # Enable a reasonable set of sanitizers. Use the linux task for that, as - # it's one of the fastest tasks (without sanitizers). Also several of the - # sanitizers work best on linux. - # - # The overhead of alignment sanitizer is low, undefined behaviour has - # moderate overhead. Test alignment sanitizer in the meson task, as it - # does both 32 and 64 bit builds and is thus more likely to expose - # alignment bugs. - # - # Address sanitizer in contrast is somewhat expensive. Enable it in the - # autoconf task, as the meson task tests both 32 and 64bit. - # - # disable_coredump=0, abort_on_error=1: for useful backtraces in case of crashes - # print_stacktraces=1,verbosity=2, duh - # detect_leaks=0: too many uninteresting leak errors in short-lived binaries - UBSAN_OPTIONS: print_stacktrace=1:disable_coredump=0:abort_on_error=1:verbosity=2 - ASAN_OPTIONS: print_stacktrace=1:disable_coredump=0:abort_on_error=1:detect_leaks=0 - - # SANITIZER_FLAGS is set in the tasks below - CFLAGS: -Og -ggdb -fno-sanitize-recover=all $SANITIZER_FLAGS - CXXFLAGS: $CFLAGS - LDFLAGS: $SANITIZER_FLAGS - CC: ccache gcc - CXX: ccache g++ - - LINUX_CONFIGURE_FEATURES: *LINUX_CONFIGURE_FEATURES - LINUX_MESON_FEATURES: >- - -Duuid=e2fs - - <<: *linux_task_template - - depends_on: SanityCheck - only_if: $CI_LINUX_ENABLED - - ccache_cache: - folder: ${CCACHE_DIR} - - sysinfo_script: | - id - uname -a - cat /proc/cmdline - ulimit -a -H && ulimit -a -S - export - create_user_script: | - useradd -m postgres - chown -R postgres:postgres . - mkdir -p ${CCACHE_DIR} - chown -R postgres:postgres ${CCACHE_DIR} - echo '* - memlock 134217728' > /etc/security/limits.d/postgres.conf - su postgres -c "ulimit -l -H && ulimit -l -S" - setup_core_files_script: | - mkdir -m 770 /tmp/cores - chown root:postgres /tmp/cores - sysctl kernel.core_pattern='/tmp/cores/%e-%s-%p.core' - - setup_hosts_file_script: | - cat >> /etc/hosts <<-EOF - 127.0.0.1 pg-loadbalancetest - 127.0.0.2 pg-loadbalancetest - 127.0.0.3 pg-loadbalancetest - EOF - - setup_additional_packages_script: | - #apt-get update - #DEBIAN_FRONTEND=noninteractive apt-get -y install ... - - matrix: - # SPECIAL: - # - Uses address sanitizer, sanitizer failures are typically printed in - # the server log - # - Configures postgres with a small segment size - - name: Linux - Debian Trixie - Autoconf - - env: - SANITIZER_FLAGS: -fsanitize=address - PG_TEST_PG_COMBINEBACKUP_MODE: --copy-file-range - - # Normally, the "relation segment" code basically has no coverage in our - # tests, because we (quite reasonably) don't generate tables large - # enough in tests. We've had plenty bugs that we didn't notice due the - # code not being exercised much. Thus specify a very small segment size - # here. Use a non-power-of-two segment size, given we currently allow - # that. - configure_script: | - su postgres <<-EOF - set -e - ./configure \ - --enable-cassert --enable-injection-points --enable-debug \ - --enable-tap-tests --enable-nls \ - --with-segsize-blocks=6 \ - --with-libnuma \ - --with-liburing \ - \ - ${LINUX_CONFIGURE_FEATURES} \ - \ - CLANG="ccache clang" - EOF - build_script: su postgres -c "make -s -j${BUILD_JOBS} world-bin" - upload_caches: ccache - - test_world_script: | - su postgres <<-EOF - set -e - ulimit -c unlimited # default is 0 - make -s ${CHECK} ${CHECKFLAGS} -j${TEST_JOBS} - EOF - - on_failure: - <<: *on_failure_ac - - # SPECIAL: - # - Uses undefined behaviour and alignment sanitizers, sanitizer failures - # are typically printed in the server log - # - Test both 64bit and 32 bit builds - # - uses io_method=io_uring - # - Uses meson feature autodetection - - name: Linux - Debian Trixie - Meson - - env: - CCACHE_MAXSIZE: "400M" # tests two different builds - SANITIZER_FLAGS: -fsanitize=alignment,undefined - PG_TEST_INITDB_EXTRA_OPTS: >- - -c io_method=io_uring - - configure_script: | - su postgres <<-EOF - set -e - meson setup \ - ${MESON_COMMON_PG_CONFIG_ARGS} \ - --buildtype=debug \ - ${LINUX_MESON_FEATURES} -Dllvm=enabled \ - build - EOF - - # Also build & test in a 32bit build - it's gotten rare to test that - # locally. - configure_32_script: | - su postgres <<-EOF - set -e - export CC='ccache gcc -m32' - export CXX='ccache g++ -m32' - meson setup \ - ${MESON_COMMON_PG_CONFIG_ARGS} \ - --buildtype=debug \ - --pkg-config-path /usr/lib/i386-linux-gnu/pkgconfig/ \ - -DPERL=perl5.40-i386-linux-gnu \ - ${LINUX_MESON_FEATURES} -Dlibnuma=disabled \ - build-32 - EOF - - build_script: | - su postgres <<-EOF - set -e - ninja -C build -j${BUILD_JOBS} ${MBUILD_TARGET} - ninja -C build -t missingdeps - EOF - - build_32_script: | - su postgres <<-EOF - set -e - ninja -C build-32 -j${BUILD_JOBS} ${MBUILD_TARGET} - ninja -C build -t missingdeps - EOF - - upload_caches: ccache - - test_world_script: | - su postgres <<-EOF - set -e - ulimit -c unlimited - meson test $MTEST_ARGS --num-processes ${TEST_JOBS} - EOF - # so that we don't upload 64bit logs if 32bit fails - rm -rf build/ - - # There's currently no coverage of icu with LANG=C in the buildfarm. We - # can easily provide some here by running one of the sets of tests that - # way. Newer versions of python insist on changing the LC_CTYPE away - # from C, prevent that with PYTHONCOERCECLOCALE. - test_world_32_script: | - su postgres <<-EOF - set -e - ulimit -c unlimited - PYTHONCOERCECLOCALE=0 LANG=C meson test $MTEST_ARGS -C build-32 --num-processes ${TEST_JOBS} - EOF - - on_failure: - <<: *on_failure_meson - - on_failure: - cores_script: src/tools/ci/cores_backtrace.sh linux /tmp/cores - - -# NB: macOS is by far the most expensive OS to run CI for, therefore no -# expensive additional checks should be added. -# -# SPECIAL: -# - Enables --clone for pg_upgrade and pg_combinebackup -task: - name: macOS - Sequoia - Meson - - env: - CPUS: 4 # always get that much for cirrusci macOS instances - BUILD_JOBS: $CPUS - # Test performance regresses noticeably when using all cores. 8 seems to - # work OK. See - # https://postgr.es/m/20220927040208.l3shfcidovpzqxfh%40awork3.anarazel.de - TEST_JOBS: 8 - IMAGE: ghcr.io/cirruslabs/macos-runner:sequoia - - CIRRUS_WORKING_DIR: ${HOME}/pgsql/ - CCACHE_DIR: ${HOME}/ccache - MACPORTS_CACHE: ${HOME}/macports-cache - - MESON_FEATURES: >- - -Dbonjour=enabled - -Ddtrace=enabled - -Dgssapi=enabled - -Dlibcurl=enabled - -Dnls=enabled - -Duuid=e2fs - - MACOS_PACKAGE_LIST: >- - ccache - icu - kerberos5 - lz4 - meson - openldap - openssl - p5.34-io-tty - p5.34-ipc-run - python312 - tcl - zstd - - CC: ccache cc - CXX: ccache c++ - CFLAGS: -Og -ggdb - CXXFLAGS: -Og -ggdb - - PG_TEST_PG_UPGRADE_MODE: --clone - PG_TEST_PG_COMBINEBACKUP_MODE: --clone - - <<: *macos_task_template - - depends_on: SanityCheck - only_if: $CI_MACOS_ENABLED - - sysinfo_script: | - id - uname -a - ulimit -a -H && ulimit -a -S - export - - setup_core_files_script: - - mkdir ${HOME}/cores - - sudo sysctl kern.corefile="${HOME}/cores/core.%P" - - # Use macports, even though homebrew is installed. The installation - # of the additional packages we need would take quite a while with - # homebrew, even if we cache the downloads. We can't cache all of - # homebrew, because it's already large. So we use macports. To cache - # the installation we create a .dmg file that we mount if it already - # exists. - # XXX: The reason for the direct p5.34* references is that we'd need - # the large macport tree around to figure out that p5-io-tty is - # actually p5.34-io-tty. Using the unversioned name works, but - # updates macports every time. - macports_cache: - folder: ${MACPORTS_CACHE} - fingerprint_script: | - # Reinstall packages if the OS major version, the list of the packages - # to install or the MacPorts install script changes. - sw_vers -productVersion | sed 's/\..*//' - echo $MACOS_PACKAGE_LIST - md5 src/tools/ci/ci_macports_packages.sh - reupload_on_changes: true - setup_additional_packages_script: | - sh src/tools/ci/ci_macports_packages.sh $MACOS_PACKAGE_LIST - # system python doesn't provide headers - sudo /opt/local/bin/port select python3 python312 - # Make macports install visible for subsequent steps - echo PATH=/opt/local/sbin/:/opt/local/bin/:$PATH >> $CIRRUS_ENV - upload_caches: macports - - ccache_cache: - folder: $CCACHE_DIR - configure_script: | - export PKG_CONFIG_PATH="/opt/local/lib/pkgconfig/" - meson setup \ - ${MESON_COMMON_PG_CONFIG_ARGS} \ - --buildtype=debug \ - -Dextra_include_dirs=/opt/local/include \ - -Dextra_lib_dirs=/opt/local/lib \ - ${MESON_COMMON_FEATURES} ${MESON_FEATURES} \ - build - - build_script: ninja -C build -j${BUILD_JOBS} ${MBUILD_TARGET} - upload_caches: ccache - - test_world_script: | - ulimit -c unlimited # default is 0 - ulimit -n 1024 # default is 256, pretty low - meson test $MTEST_ARGS --num-processes ${TEST_JOBS} - - on_failure: - <<: *on_failure_meson - cores_script: src/tools/ci/cores_backtrace.sh macos "${HOME}/cores" - - -WINDOWS_ENVIRONMENT_BASE: &WINDOWS_ENVIRONMENT_BASE - env: - # Half the allowed per-user CPU cores - CPUS: 4 - - # The default cirrus working dir is in a directory msbuild complains about - CIRRUS_WORKING_DIR: "c:/cirrus" - # git's tar doesn't deal with drive letters, see - # https://postgr.es/m/b6782dc3-a7b0-ed56-175f-f8f54cb08d67%40dunslane.net - TAR: "c:/windows/system32/tar.exe" - # Avoids port conflicts between concurrent tap test runs - PG_TEST_USE_UNIX_SOCKETS: 1 - PG_REGRESS_SOCK_DIR: "c:/cirrus/" - DISK_SIZE: 50 - IMAGE_FAMILY: pg-ci-windows-ci - - sysinfo_script: | - chcp - systeminfo - powershell -Command get-psdrive -psprovider filesystem - set - - -task: - name: Windows - Server 2022, VS 2019 - Meson & ninja - << : *WINDOWS_ENVIRONMENT_BASE - - env: - TEST_JOBS: 8 # wild guess, data based value welcome - - # Cirrus defaults to SetErrorMode(SEM_NOGPFAULTERRORBOX | ...). That - # prevents crash reporting from working unless binaries do SetErrorMode() - # themselves. Furthermore, it appears that either python or, more likely, - # the C runtime has a bug where SEM_NOGPFAULTERRORBOX can very - # occasionally *trigger* a crash on process exit - which is hard to debug, - # given that it explicitly prevents crash dumps from working... - # 0x8001 is SEM_FAILCRITICALERRORS | SEM_NOOPENFILEERRORBOX - CIRRUS_WINDOWS_ERROR_MODE: 0x8001 - - MESON_FEATURES: - -Dcpp_args=/std:c++20 - -Dauto_features=disabled - -Dldap=enabled - -Dssl=openssl - -Dtap_tests=enabled - -Dplperl=enabled - -Dplpython=enabled - - <<: *windows_task_template - - depends_on: SanityCheck - only_if: $CI_WINDOWS_ENABLED - - setup_additional_packages_script: | - REM choco install -y --no-progress ... - - setup_hosts_file_script: | - echo 127.0.0.1 pg-loadbalancetest >> c:\Windows\System32\Drivers\etc\hosts - echo 127.0.0.2 pg-loadbalancetest >> c:\Windows\System32\Drivers\etc\hosts - echo 127.0.0.3 pg-loadbalancetest >> c:\Windows\System32\Drivers\etc\hosts - type c:\Windows\System32\Drivers\etc\hosts - - configure_script: | - vcvarsall x64 - meson setup --backend ninja %MESON_COMMON_PG_CONFIG_ARGS% --buildtype debug -Db_pch=true -Dextra_lib_dirs=c:\openssl\1.1\lib -Dextra_include_dirs=c:\openssl\1.1\include -DTAR=%TAR% %MESON_FEATURES% build - - build_script: | - vcvarsall x64 - ninja -C build %MBUILD_TARGET% - ninja -C build -t missingdeps - - check_world_script: | - vcvarsall x64 - meson test %MTEST_ARGS% --num-processes %TEST_JOBS% - - on_failure: - <<: *on_failure_meson - crashlog_artifacts: - path: "crashlog-*.txt" - type: text/plain - - -task: - << : *WINDOWS_ENVIRONMENT_BASE - name: Windows - Server 2022, MinGW64 - Meson - - # See REPO_CI_AUTOMATIC_TRIGGER_TASKS in .cirrus.star. - trigger_type: $CI_TRIGGER_TYPE_MINGW - - depends_on: SanityCheck - only_if: $CI_MINGW_ENABLED - - env: - TEST_JOBS: 4 # higher concurrency causes occasional failures - CCACHE_DIR: C:/msys64/ccache - CCACHE_MAXSIZE: "500M" - CCACHE_SLOPPINESS: pch_defines,time_macros - CCACHE_DEPEND: 1 - # for some reason mingw plpython cannot find its installation without this - PYTHONHOME: C:/msys64/ucrt64 - # prevents MSYS bash from resetting error mode - MSYS: winjitdebug - # Start bash in current working directory - CHERE_INVOKING: 1 - BASH: C:\msys64\usr\bin\bash.exe -l - - # Keep -Dnls explicitly disabled, as the number of files it creates causes a - # noticeable slowdown. - MESON_FEATURES: >- - -Dnls=disabled - - <<: *windows_task_template - - ccache_cache: - folder: ${CCACHE_DIR} - - setup_additional_packages_script: | - REM C:\msys64\usr\bin\pacman.exe -S --noconfirm ... - - mingw_info_script: | - %BASH% -c "where gcc" - %BASH% -c "gcc --version" - %BASH% -c "where perl" - %BASH% -c "perl --version" - - configure_script: | - %BASH% -c "meson setup %MESON_COMMON_PG_CONFIG_ARGS% -Ddebug=true -Doptimization=g -Db_pch=true %MESON_COMMON_FEATURES% %MESON_FEATURES% -DTAR=%TAR% build" - - build_script: | - %BASH% -c "ninja -C build ${MBUILD_TARGET}" - - upload_caches: ccache - - test_world_script: | - %BASH% -c "meson test %MTEST_ARGS% --num-processes %TEST_JOBS%" - - on_failure: - <<: *on_failure_meson - crashlog_artifacts: - path: "crashlog-*.txt" - type: text/plain - - -task: - name: CompilerWarnings - - # To limit unnecessary work only run this once the SanityCheck - # succeeds. This is particularly important for this task as we intentionally - # use always: to continue after failures. - depends_on: SanityCheck - only_if: $CI_COMPILERWARNINGS_ENABLED - - env: - CPUS: 4 - BUILD_JOBS: 4 - IMAGE_FAMILY: pg-ci-trixie - - # Use larger ccache cache, as this task compiles with multiple compilers / - # flag combinations - CCACHE_MAXSIZE: "1G" - CCACHE_DIR: "/tmp/ccache_dir" - - LINUX_CONFIGURE_FEATURES: *LINUX_CONFIGURE_FEATURES - - <<: *linux_task_template - - sysinfo_script: | - id - uname -a - cat /proc/cmdline - ulimit -a -H && ulimit -a -S - gcc -v - clang -v - export - - ccache_cache: - folder: $CCACHE_DIR - - setup_additional_packages_script: | - #apt-get update - #DEBIAN_FRONTEND=noninteractive apt-get -y install ... - - ### - # Test that code can be built with gcc/clang without warnings - ### - - setup_script: echo "COPT=-Werror" > src/Makefile.custom - - # Trace probes have a history of getting accidentally broken. Use the - # different compilers to build with different combinations of dtrace on/off - # and cassert on/off. - - # gcc, cassert off, dtrace on - always: - gcc_warning_script: | - time ./configure \ - --cache gcc.cache \ - --enable-dtrace \ - ${LINUX_CONFIGURE_FEATURES} \ - CC="ccache gcc" CXX="ccache g++" CLANG="ccache clang" - make -s -j${BUILD_JOBS} clean - time make -s -j${BUILD_JOBS} world-bin - - # gcc, cassert on, dtrace off - always: - gcc_a_warning_script: | - time ./configure \ - --cache gcc.cache \ - --enable-cassert \ - ${LINUX_CONFIGURE_FEATURES} \ - CC="ccache gcc" CXX="ccache g++" CLANG="ccache clang" - make -s -j${BUILD_JOBS} clean - time make -s -j${BUILD_JOBS} world-bin - - # clang, cassert off, dtrace off - always: - clang_warning_script: | - time ./configure \ - --cache clang.cache \ - ${LINUX_CONFIGURE_FEATURES} \ - CC="ccache clang" CXX="ccache clang++" CLANG="ccache clang" - make -s -j${BUILD_JOBS} clean - time make -s -j${BUILD_JOBS} world-bin - - # clang, cassert on, dtrace on - always: - clang_a_warning_script: | - time ./configure \ - --cache clang.cache \ - --enable-cassert \ - --enable-dtrace \ - ${LINUX_CONFIGURE_FEATURES} \ - CC="ccache clang" CXX="ccache clang++" CLANG="ccache clang" - make -s -j${BUILD_JOBS} clean - time make -s -j${BUILD_JOBS} world-bin - - # cross-compile to windows - always: - mingw_cross_warning_script: | - time ./configure \ - --host=x86_64-w64-mingw32ucrt \ - --enable-cassert \ - --without-icu \ - CC="ccache x86_64-w64-mingw32ucrt-gcc" \ - CXX="ccache x86_64-w64-mingw32ucrt-g++" - make -s -j${BUILD_JOBS} clean - time make -s -j${BUILD_JOBS} world-bin - - ### - # Verify docs can be built - ### - # XXX: Only do this if there have been changes in doc/ since last build - always: - docs_build_script: | - time ./configure \ - --cache gcc.cache \ - CC="ccache gcc" CXX="ccache g++" CLANG="ccache clang" - make -s -j${BUILD_JOBS} clean - time make -s -j${BUILD_JOBS} -C doc - - ### - # Verify headerscheck / cpluspluscheck succeed - # - # - Run both in same script to increase parallelism, use -k to get result of both - # - Use -fmax-errors, as particularly cpluspluscheck can be very verbose - ### - always: - headers_headerscheck_script: | - time ./configure \ - ${LINUX_CONFIGURE_FEATURES} \ - --cache gcc.cache \ - --quiet \ - CC="ccache gcc" CXX="ccache g++" CLANG="ccache clang" - make -s -j${BUILD_JOBS} clean - time make -s -j${BUILD_JOBS} -k ${CHECKFLAGS} headerscheck cpluspluscheck EXTRAFLAGS='-fmax-errors=10' - - always: - upload_caches: ccache diff --git a/src/tools/ci/ci_macports_packages.sh b/src/tools/ci/ci_macports_packages.sh index e49f4f703a0..092d8cd7e8f 100755 --- a/src/tools/ci/ci_macports_packages.sh +++ b/src/tools/ci/ci_macports_packages.sh @@ -6,8 +6,7 @@ # when packages are installed or removed. Any package this script is # not instructed to install, will be removed again. # -# This currently expects to be run in a GitHub Actions or cirrus-ci -# macOS environment. +# This currently expects to be run in a GitHub Actions macOS environment. set -e # set -x @@ -39,8 +38,8 @@ fi cache_dmg="macports.hfs.dmg" -if [ "$CIRRUS_CI" != "true" ] && [ "$GITHUB_ACTIONS" != "true" ]; then - echo "expect to be called within cirrus-ci or GitHub Actions" 1>&2 +if [ "$GITHUB_ACTIONS" != "true" ]; then + echo "expect to be called within GitHub Actions" 1>&2 exit 1 fi diff --git a/src/tools/ci/gcp_ram_disk.sh b/src/tools/ci/gcp_ram_disk.sh deleted file mode 100755 index 18dbb2037f5..00000000000 --- a/src/tools/ci/gcp_ram_disk.sh +++ /dev/null @@ -1,27 +0,0 @@ -#!/bin/sh -# Move working directory into a RAM disk for better performance. - -set -e -set -x - -mv $CIRRUS_WORKING_DIR $CIRRUS_WORKING_DIR.orig -mkdir $CIRRUS_WORKING_DIR - -case "`uname`" in - FreeBSD|NetBSD) - mount -t tmpfs tmpfs $CIRRUS_WORKING_DIR - ;; - OpenBSD) - umount /dev/sd0j # unused /usr/obj partition - printf "m j\n\n\nswap\nw\nq\n" | disklabel -E sd0 - swapon /dev/sd0j - # Remove the per-process data segment limit so that mount_mfs can allocate - # large memory filesystems. Without this, mount_mfs mmap() may fail with - # "Cannot allocate memory" if the requested size exceeds the current - # datasize limit. - ulimit -d unlimited - mount -t mfs -o rw,noatime,nodev,-s=10000000 swap $CIRRUS_WORKING_DIR - ;; -esac - -cp -a $CIRRUS_WORKING_DIR.orig/. $CIRRUS_WORKING_DIR/ -- 2.54.0.380.gc69baaf57b --vdbxiaou22xpj6rk-- ^ permalink raw reply [nested|flat] 354+ messages in thread
end of thread, other threads:[~2026-06-04 13:34 UTC | newest] Thread overview: 354+ 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 <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-03-24 14:09 [PATCH v44 07/10] Split cluster.h to create repack_internal.h Álvaro Herrera <alvherre@kurilemu.de> 2026-06-04 13:34 [PATCH v11a 2/2] ci: Remove support for cirrus-ci based CI Andres Freund <andres@anarazel.de>
This inbox is served by agora; see mirroring instructions for how to clone and mirror all data and code used for this inbox