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* [PATCH v4 1/2] In-place table persistence change
@ 2020-11-11 12:51 Kyotaro Horiguchi <[email protected]>
0 siblings, 0 replies; 3+ messages in thread
From: Kyotaro Horiguchi @ 2020-11-11 12:51 UTC (permalink / raw)
Even though ALTER TABLE SET LOGGED/UNLOGGED does not require data
rewriting, currently it runs heap rewrite which causes large amount of
file I/O. This patch makes the command run without heap rewrite.
Addition to that, SET LOGGED while wal_level > minimal emits WAL using
XLOG_FPI instead of massive number of HEAP_INSERT's, which should be
smaller.
Also this allows for the cleanup of files left behind in the crash of
the transaction that created it.
---
src/backend/access/rmgrdesc/smgrdesc.c | 23 ++
src/backend/access/transam/README | 8 +
src/backend/access/transam/xlog.c | 17 +
src/backend/catalog/storage.c | 436 +++++++++++++++++++++++--
src/backend/commands/tablecmds.c | 246 +++++++++++---
src/backend/storage/buffer/bufmgr.c | 88 +++++
src/backend/storage/file/reinit.c | 322 ++++++++++++------
src/backend/storage/smgr/md.c | 13 +-
src/backend/storage/smgr/smgr.c | 6 +
src/common/relpath.c | 4 +-
src/include/catalog/storage.h | 2 +
src/include/catalog/storage_xlog.h | 22 +-
src/include/common/relpath.h | 6 +-
src/include/storage/bufmgr.h | 2 +
src/include/storage/md.h | 2 +
src/include/storage/reinit.h | 3 +-
src/include/storage/smgr.h | 1 +
17 files changed, 1034 insertions(+), 167 deletions(-)
diff --git a/src/backend/access/rmgrdesc/smgrdesc.c b/src/backend/access/rmgrdesc/smgrdesc.c
index 7755553d57..2c109b8ca4 100644
--- a/src/backend/access/rmgrdesc/smgrdesc.c
+++ b/src/backend/access/rmgrdesc/smgrdesc.c
@@ -40,6 +40,23 @@ smgr_desc(StringInfo buf, XLogReaderState *record)
xlrec->blkno, xlrec->flags);
pfree(path);
}
+ else if (info == XLOG_SMGR_UNLINK)
+ {
+ xl_smgr_unlink *xlrec = (xl_smgr_unlink *) rec;
+ char *path = relpathperm(xlrec->rnode, xlrec->forkNum);
+
+ appendStringInfoString(buf, path);
+ pfree(path);
+ }
+ else if (info == XLOG_SMGR_BUFPERSISTENCE)
+ {
+ xl_smgr_bufpersistence *xlrec = (xl_smgr_bufpersistence *) rec;
+ char *path = relpathperm(xlrec->rnode, MAIN_FORKNUM);
+
+ appendStringInfoString(buf, path);
+ appendStringInfo(buf, " persistence %d", xlrec->persistence);
+ pfree(path);
+ }
}
const char *
@@ -55,6 +72,12 @@ smgr_identify(uint8 info)
case XLOG_SMGR_TRUNCATE:
id = "TRUNCATE";
break;
+ case XLOG_SMGR_UNLINK:
+ id = "UNLINK";
+ break;
+ case XLOG_SMGR_BUFPERSISTENCE:
+ id = "BUFPERSISTENCE";
+ break;
}
return id;
diff --git a/src/backend/access/transam/README b/src/backend/access/transam/README
index 1edc8180c1..547107a771 100644
--- a/src/backend/access/transam/README
+++ b/src/backend/access/transam/README
@@ -724,6 +724,14 @@ we must panic and abort recovery. The DBA will have to manually clean up
then restart recovery. This is part of the reason for not writing a WAL
entry until we've successfully done the original action.
+The CLEANUP fork file
+--------------------------------
+
+An CLEANUP fork is created when a new relation file is created to mark
+the relfilenode needs to be cleaned up at recovery time. In contrast
+to 4 above, failure to remove an CLEANUP fork file will lead to data
+loss, in which case the server will shut down.
+
Skipping WAL for New RelFileNode
--------------------------------
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index b18257c198..6dcbcbe387 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -40,6 +40,7 @@
#include "catalog/catversion.h"
#include "catalog/pg_control.h"
#include "catalog/pg_database.h"
+#include "catalog/storage.h"
#include "commands/progress.h"
#include "commands/tablespace.h"
#include "common/controldata_utils.h"
@@ -4442,6 +4443,14 @@ ReadRecord(XLogReaderState *xlogreader, int emode,
{
ereport(DEBUG1,
(errmsg_internal("reached end of WAL in pg_wal, entering archive recovery")));
+
+ /* cleanup garbage files left during crash recovery */
+ ResetUnloggedRelations(UNLOGGED_RELATION_DROP_BUFFER |
+ UNLOGGED_RELATION_CLEANUP);
+
+ /* run rollback cleanup if any */
+ smgrDoPendingDeletes(false);
+
InArchiveRecovery = true;
if (StandbyModeRequested)
StandbyMode = true;
@@ -7455,6 +7464,14 @@ StartupXLOG(void)
}
}
+ /* cleanup garbage files left during crash recovery */
+ if (!InArchiveRecovery)
+ ResetUnloggedRelations(UNLOGGED_RELATION_DROP_BUFFER |
+ UNLOGGED_RELATION_CLEANUP);
+
+ /* run rollback cleanup if any */
+ smgrDoPendingDeletes(false);
+
/* Allow resource managers to do any required cleanup. */
for (rmid = 0; rmid <= RM_MAX_ID; rmid++)
{
diff --git a/src/backend/catalog/storage.c b/src/backend/catalog/storage.c
index cba7a9ada0..c54d70747f 100644
--- a/src/backend/catalog/storage.c
+++ b/src/backend/catalog/storage.c
@@ -19,6 +19,7 @@
#include "postgres.h"
+#include "access/amapi.h"
#include "access/parallel.h"
#include "access/visibilitymap.h"
#include "access/xact.h"
@@ -27,6 +28,7 @@
#include "access/xlogutils.h"
#include "catalog/storage.h"
#include "catalog/storage_xlog.h"
+#include "common/hashfn.h"
#include "miscadmin.h"
#include "storage/freespace.h"
#include "storage/smgr.h"
@@ -57,9 +59,16 @@ int wal_skip_threshold = 2048; /* in kilobytes */
* but I'm being paranoid.
*/
+#define PDOP_DELETE (0)
+#define PDOP_UNLINK_FORK (1 << 0)
+#define PDOP_SET_PERSISTENCE (1 << 1)
+
typedef struct PendingRelDelete
{
RelFileNode relnode; /* relation that may need to be deleted */
+ int op; /* operation mask */
+ bool bufpersistence; /* buffer persistence to set */
+ int unlink_forknum; /* forknum to unlink */
BackendId backend; /* InvalidBackendId if not a temp rel */
bool atCommit; /* T=delete at commit; F=delete at abort */
int nestLevel; /* xact nesting level of request */
@@ -75,6 +84,24 @@ typedef struct PendingRelSync
static PendingRelDelete *pendingDeletes = NULL; /* head of linked list */
HTAB *pendingSyncHash = NULL;
+typedef struct SRelHashEntry
+{
+ SMgrRelation srel;
+ char status; /* for simplehash use */
+} SRelHashEntry;
+
+/* define hashtable for workarea for pending deletes */
+#define SH_PREFIX srelhash
+#define SH_ELEMENT_TYPE SRelHashEntry
+#define SH_KEY_TYPE SMgrRelation
+#define SH_KEY srel
+#define SH_HASH_KEY(tb, key) \
+ hash_bytes((unsigned char *)&key, sizeof(SMgrRelation))
+#define SH_EQUAL(tb, a, b) (memcmp(&a, &b, sizeof(SMgrRelation)) == 0)
+#define SH_SCOPE static inline
+#define SH_DEFINE
+#define SH_DECLARE
+#include "lib/simplehash.h"
/*
* AddPendingSync
@@ -143,7 +170,17 @@ RelationCreateStorage(RelFileNode rnode, char relpersistence)
return NULL; /* placate compiler */
}
+ /*
+ * We are going to create a new storage file. If server crashes before the
+ * current transaction ends the file needs to be cleaned up but there's no
+ * clue to the orphan files. The cleanup fork works as the sentinel to
+ * identify that situation.
+ */
srel = smgropen(rnode, backend);
+ smgrcreate(srel, CLEANUP2_FORKNUM, false);
+ log_smgrcreate(&rnode, CLEANUP2_FORKNUM);
+ smgrimmedsync(srel, CLEANUP2_FORKNUM);
+
smgrcreate(srel, MAIN_FORKNUM, false);
if (needs_wal)
@@ -153,12 +190,25 @@ RelationCreateStorage(RelFileNode rnode, char relpersistence)
pending = (PendingRelDelete *)
MemoryContextAlloc(TopMemoryContext, sizeof(PendingRelDelete));
pending->relnode = rnode;
+ pending->op = PDOP_DELETE;
pending->backend = backend;
pending->atCommit = false; /* delete if abort */
pending->nestLevel = GetCurrentTransactionNestLevel();
pending->next = pendingDeletes;
pendingDeletes = pending;
+ /* drop cleanup fork at commit */
+ pending = (PendingRelDelete *)
+ MemoryContextAlloc(TopMemoryContext, sizeof(PendingRelDelete));
+ pending->relnode = rnode;
+ pending->op = PDOP_UNLINK_FORK;
+ pending->unlink_forknum = CLEANUP2_FORKNUM;
+ pending->backend = backend;
+ pending->atCommit = true;
+ pending->nestLevel = GetCurrentTransactionNestLevel();
+ pending->next = pendingDeletes;
+ pendingDeletes = pending;
+
if (relpersistence == RELPERSISTENCE_PERMANENT && !XLogIsNeeded())
{
Assert(backend == InvalidBackendId);
@@ -168,6 +218,218 @@ RelationCreateStorage(RelFileNode rnode, char relpersistence)
return srel;
}
+/*
+ * RelationCreateInitFork
+ * Create physical storage for the init fork of a relation.
+ *
+ * Create the init fork for the relation.
+ *
+ * This function is transactional. The creation is WAL-logged, and if the
+ * transaction aborts later on, the init fork will be removed.
+ */
+void
+RelationCreateInitFork(Relation rel)
+{
+ RelFileNode rnode = rel->rd_node;
+ PendingRelDelete *pending;
+ SMgrRelation srel;
+ PendingRelDelete *prev;
+ PendingRelDelete *next;
+ bool create = true;
+
+ /* switch buffer persistence */
+ SetRelationBuffersPersistence(rel->rd_smgr, false, false);
+
+ /*
+ * If we have entries for init-fork operation of this relation, that means
+ * that we have already registered pending delete entries to drop
+ * preexisting init fork since before the current transaction started. This
+ * function reverts that change just by removing the entries.
+ */
+ prev = NULL;
+ for (pending = pendingDeletes; pending != NULL; pending = next)
+ {
+ next = pending->next;
+ if (RelFileNodeEquals(rnode, pending->relnode) &&
+ pending->op != PDOP_DELETE &&
+ ((pending->op & PDOP_UNLINK_FORK) != 0 &&
+ pending->unlink_forknum == CLEANUP_FORKNUM))
+ {
+ if (prev)
+ prev->next = next;
+ else
+ pendingDeletes = next;
+ pfree(pending);
+
+ create = false;
+ }
+ else
+ {
+ /* unrelated entry, don't touch it */
+ prev = pending;
+ }
+ }
+
+ if (!create)
+ return;
+
+ /*
+ * We are going to create the init fork. If server crashes before the
+ * current transaction ends the init fork left alone corrupts data while
+ * recovery. The cleanup fork works as the sentinel to identify that
+ * situation.
+ */
+ srel = smgropen(rnode, InvalidBackendId);
+ smgrcreate(srel, CLEANUP_FORKNUM, false);
+ log_smgrcreate(&rnode, CLEANUP_FORKNUM);
+ smgrimmedsync(srel, CLEANUP_FORKNUM);
+
+ /* We don't have existing init fork, create it. */
+ smgrcreate(srel, INIT_FORKNUM, false);
+
+ /*
+ * index-init fork needs further initialization. ambuildempty shoud do
+ * WAL-log and file sync by itself but otherwise we do that by myself.
+ */
+ if (rel->rd_rel->relkind == RELKIND_INDEX)
+ rel->rd_indam->ambuildempty(rel);
+ else
+ {
+ log_smgrcreate(&rnode, INIT_FORKNUM);
+ smgrimmedsync(srel, INIT_FORKNUM);
+ }
+
+ /* drop this init fork file at abort and revert persistence */
+ pending = (PendingRelDelete *)
+ MemoryContextAlloc(TopMemoryContext, sizeof(PendingRelDelete));
+ pending->relnode = rnode;
+ pending->op = PDOP_UNLINK_FORK | PDOP_SET_PERSISTENCE;
+ pending->unlink_forknum = INIT_FORKNUM;
+ pending->bufpersistence = true;
+ pending->backend = InvalidBackendId;
+ pending->atCommit = false;
+ pending->nestLevel = GetCurrentTransactionNestLevel();
+ pending->next = pendingDeletes;
+ pendingDeletes = pending;
+
+ /* drop cleanup fork at abort */
+ pending = (PendingRelDelete *)
+ MemoryContextAlloc(TopMemoryContext, sizeof(PendingRelDelete));
+ pending->relnode = rnode;
+ pending->op = PDOP_UNLINK_FORK;
+ pending->unlink_forknum = CLEANUP_FORKNUM;
+ pending->backend = InvalidBackendId;
+ pending->atCommit = false;
+ pending->nestLevel = GetCurrentTransactionNestLevel();
+ pending->next = pendingDeletes;
+ pendingDeletes = pending;
+
+ /* drop cleanup fork at commit */
+ pending = (PendingRelDelete *)
+ MemoryContextAlloc(TopMemoryContext, sizeof(PendingRelDelete));
+ pending->relnode = rnode;
+ pending->op = PDOP_UNLINK_FORK;
+ pending->unlink_forknum = CLEANUP_FORKNUM;
+ pending->backend = InvalidBackendId;
+ pending->atCommit = true;
+ pending->nestLevel = GetCurrentTransactionNestLevel();
+ pending->next = pendingDeletes;
+ pendingDeletes = pending;
+}
+
+/*
+ * RelationDropInitFork
+ * Delete physical storage for the init fork of a relation.
+ *
+ * Register pending-delete of the init fork. The real deletion is performed by
+ * smgrDoPendingDeletes at commit.
+ *
+ * This function is transactional. If the transaction aborts later on, the
+ * deletion doesn't happen.
+ */
+void
+RelationDropInitFork(Relation rel)
+{
+ RelFileNode rnode = rel->rd_node;
+ PendingRelDelete *pending;
+ PendingRelDelete *prev;
+ PendingRelDelete *next;
+ bool inxact_created = false;
+
+ /* switch buffer persistence */
+ SetRelationBuffersPersistence(rel->rd_smgr, true, false);
+
+ /*
+ * If we have entries for init-fork operation of this relation, that means
+ * that we have created the init fork in the current transaction. We
+ * immediately remove the init and cleanup forks immediately in that case.
+ * Otherwise just reister pending-delete for the existing init fork.
+ */
+ prev = NULL;
+ for (pending = pendingDeletes; pending != NULL; pending = next)
+ {
+ next = pending->next;
+ if (RelFileNodeEquals(rnode, pending->relnode) &&
+ pending->op != PDOP_DELETE &&
+ ((pending->op & PDOP_UNLINK_FORK) != 0 &&
+ pending->unlink_forknum == CLEANUP_FORKNUM))
+ {
+ /* unlink list entry */
+ if (prev)
+ prev->next = next;
+ else
+ pendingDeletes = next;
+ pfree(pending);
+
+ inxact_created = true;
+ }
+ else
+ {
+ /* unrelated entry, don't touch it */
+ prev = pending;
+ }
+ }
+
+ if (inxact_created)
+ {
+ SMgrRelation srel = smgropen(rnode, InvalidBackendId);
+
+ /*
+ * INIT/CLEANUP forks never be loaded to shared buffer so no point in
+ * dropping buffers for these files.
+ */
+ log_smgrunlink(&rnode, INIT_FORKNUM);
+ smgrunlink(srel, INIT_FORKNUM, false);
+ log_smgrunlink(&rnode, CLEANUP_FORKNUM);
+ smgrunlink(srel, CLEANUP_FORKNUM, false);
+ return;
+ }
+
+ /* register drop of this init fork file at commit */
+ pending = (PendingRelDelete *)
+ MemoryContextAlloc(TopMemoryContext, sizeof(PendingRelDelete));
+ pending->relnode = rnode;
+ pending->op = PDOP_UNLINK_FORK;
+ pending->unlink_forknum = INIT_FORKNUM;
+ pending->backend = InvalidBackendId;
+ pending->atCommit = true;
+ pending->nestLevel = GetCurrentTransactionNestLevel();
+ pending->next = pendingDeletes;
+ pendingDeletes = pending;
+
+ /* revert buffer-persistence changes at abort */
+ pending = (PendingRelDelete *)
+ MemoryContextAlloc(TopMemoryContext, sizeof(PendingRelDelete));
+ pending->relnode = rnode;
+ pending->op = PDOP_SET_PERSISTENCE;
+ pending->bufpersistence = false;
+ pending->backend = InvalidBackendId;
+ pending->atCommit = false;
+ pending->nestLevel = GetCurrentTransactionNestLevel();
+ pending->next = pendingDeletes;
+ pendingDeletes = pending;
+}
+
/*
* Perform XLogInsert of an XLOG_SMGR_CREATE record to WAL.
*/
@@ -187,6 +449,44 @@ log_smgrcreate(const RelFileNode *rnode, ForkNumber forkNum)
XLogInsert(RM_SMGR_ID, XLOG_SMGR_CREATE | XLR_SPECIAL_REL_UPDATE);
}
+/*
+ * Perform XLogInsert of an XLOG_SMGR_UNLINK record to WAL.
+ */
+void
+log_smgrunlink(const RelFileNode *rnode, ForkNumber forkNum)
+{
+ xl_smgr_unlink xlrec;
+
+ /*
+ * Make an XLOG entry reporting the file unlink.
+ */
+ xlrec.rnode = *rnode;
+ xlrec.forkNum = forkNum;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, sizeof(xlrec));
+ XLogInsert(RM_SMGR_ID, XLOG_SMGR_UNLINK | XLR_SPECIAL_REL_UPDATE);
+}
+
+/*
+ * Perform XLogInsert of an XLOG_SMGR_BUFPERSISTENCE record to WAL.
+ */
+void
+log_smgrbufpersistence(const RelFileNode *rnode, bool persistence)
+{
+ xl_smgr_bufpersistence xlrec;
+
+ /*
+ * Make an XLOG entry reporting the change of buffer persistence.
+ */
+ xlrec.rnode = *rnode;
+ xlrec.persistence = persistence;
+
+ XLogBeginInsert();
+ XLogRegisterData((char *) &xlrec, sizeof(xlrec));
+ XLogInsert(RM_SMGR_ID, XLOG_SMGR_BUFPERSISTENCE | XLR_SPECIAL_REL_UPDATE);
+}
+
/*
* RelationDropStorage
* Schedule unlinking of physical storage at transaction commit.
@@ -200,6 +500,7 @@ RelationDropStorage(Relation rel)
pending = (PendingRelDelete *)
MemoryContextAlloc(TopMemoryContext, sizeof(PendingRelDelete));
pending->relnode = rel->rd_node;
+ pending->op = PDOP_DELETE;
pending->backend = rel->rd_backend;
pending->atCommit = true; /* delete if commit */
pending->nestLevel = GetCurrentTransactionNestLevel();
@@ -602,59 +903,97 @@ smgrDoPendingDeletes(bool isCommit)
int nrels = 0,
maxrels = 0;
SMgrRelation *srels = NULL;
+ srelhash_hash *close_srels = NULL;
+ bool found;
prev = NULL;
for (pending = pendingDeletes; pending != NULL; pending = next)
{
+ SMgrRelation srel;
+
next = pending->next;
if (pending->nestLevel < nestLevel)
{
/* outer-level entries should not be processed yet */
prev = pending;
+ continue;
}
+
+ /* unlink list entry first, so we don't retry on failure */
+ if (prev)
+ prev->next = next;
else
+ pendingDeletes = next;
+
+ if (pending->atCommit != isCommit)
{
- /* unlink list entry first, so we don't retry on failure */
- if (prev)
- prev->next = next;
- else
- pendingDeletes = next;
- /* do deletion if called for */
- if (pending->atCommit == isCommit)
- {
- SMgrRelation srel;
-
- srel = smgropen(pending->relnode, pending->backend);
-
- /* allocate the initial array, or extend it, if needed */
- if (maxrels == 0)
- {
- maxrels = 8;
- srels = palloc(sizeof(SMgrRelation) * maxrels);
- }
- else if (maxrels <= nrels)
- {
- maxrels *= 2;
- srels = repalloc(srels, sizeof(SMgrRelation) * maxrels);
- }
-
- srels[nrels++] = srel;
- }
/* must explicitly free the list entry */
pfree(pending);
/* prev does not change */
+ continue;
+ }
+
+ if (close_srels == NULL)
+ close_srels = srelhash_create(CurrentMemoryContext, 32, NULL);
+
+ srel = smgropen(pending->relnode, pending->backend);
+
+ /* Uniquify the smgr relations */
+ srelhash_insert(close_srels, srel, &found);
+
+ if (pending->op != PDOP_DELETE)
+ {
+ if (pending->op & PDOP_UNLINK_FORK)
+ {
+ /* other forks needs to drop buffers */
+ Assert(pending->unlink_forknum == INIT_FORKNUM ||
+ pending->unlink_forknum == CLEANUP_FORKNUM ||
+ pending->unlink_forknum == CLEANUP2_FORKNUM);
+
+ log_smgrunlink(&pending->relnode, pending->unlink_forknum);
+ smgrunlink(srel, pending->unlink_forknum, false);
+
+ }
+
+ if (pending->op & PDOP_SET_PERSISTENCE)
+ SetRelationBuffersPersistence(srel, pending->bufpersistence,
+ InRecovery);
+ }
+ else
+ {
+ /* allocate the initial array, or extend it, if needed */
+ if (maxrels == 0)
+ {
+ maxrels = 8;
+ srels = palloc(sizeof(SMgrRelation) * maxrels);
+ }
+ else if (maxrels <= nrels)
+ {
+ maxrels *= 2;
+ srels = repalloc(srels, sizeof(SMgrRelation) * maxrels);
+ }
+
+ srels[nrels++] = srel;
}
}
if (nrels > 0)
{
smgrdounlinkall(srels, nrels, false);
-
- for (int i = 0; i < nrels; i++)
- smgrclose(srels[i]);
-
pfree(srels);
}
+
+ if (close_srels)
+ {
+ srelhash_iterator i;
+ SRelHashEntry *ent;
+
+ /* close smgr relatoins */
+ srelhash_start_iterate(close_srels, &i);
+ while ((ent = srelhash_iterate(close_srels, &i)) != NULL)
+ smgrclose(ent->srel);
+ srelhash_destroy(close_srels);
+ }
}
/*
@@ -824,7 +1163,8 @@ smgrGetPendingDeletes(bool forCommit, RelFileNode **ptr)
for (pending = pendingDeletes; pending != NULL; pending = pending->next)
{
if (pending->nestLevel >= nestLevel && pending->atCommit == forCommit
- && pending->backend == InvalidBackendId)
+ && pending->backend == InvalidBackendId
+ && pending->op == PDOP_DELETE)
nrels++;
}
if (nrels == 0)
@@ -837,7 +1177,8 @@ smgrGetPendingDeletes(bool forCommit, RelFileNode **ptr)
for (pending = pendingDeletes; pending != NULL; pending = pending->next)
{
if (pending->nestLevel >= nestLevel && pending->atCommit == forCommit
- && pending->backend == InvalidBackendId)
+ && pending->backend == InvalidBackendId &&
+ pending->op == PDOP_DELETE)
{
*rptr = pending->relnode;
rptr++;
@@ -917,6 +1258,15 @@ smgr_redo(XLogReaderState *record)
reln = smgropen(xlrec->rnode, InvalidBackendId);
smgrcreate(reln, xlrec->forkNum, true);
}
+ else if (info == XLOG_SMGR_UNLINK)
+ {
+ xl_smgr_unlink *xlrec = (xl_smgr_unlink *) XLogRecGetData(record);
+ SMgrRelation reln;
+
+ reln = smgropen(xlrec->rnode, InvalidBackendId);
+ smgrunlink(reln, xlrec->forkNum, true);
+ smgrclose(reln);
+ }
else if (info == XLOG_SMGR_TRUNCATE)
{
xl_smgr_truncate *xlrec = (xl_smgr_truncate *) XLogRecGetData(record);
@@ -1005,6 +1355,28 @@ smgr_redo(XLogReaderState *record)
FreeFakeRelcacheEntry(rel);
}
+ else if (info == XLOG_SMGR_BUFPERSISTENCE)
+ {
+ xl_smgr_bufpersistence *xlrec =
+ (xl_smgr_bufpersistence *) XLogRecGetData(record);
+ SMgrRelation reln;
+ PendingRelDelete *pending;
+
+ reln = smgropen(xlrec->rnode, InvalidBackendId);
+ SetRelationBuffersPersistence(reln, xlrec->persistence, true);
+
+ /* revert buffer-persistence changes at abort */
+ pending = (PendingRelDelete *)
+ MemoryContextAlloc(TopMemoryContext, sizeof(PendingRelDelete));
+ pending->relnode = xlrec->rnode;
+ pending->op = PDOP_SET_PERSISTENCE;
+ pending->bufpersistence = !xlrec->persistence;
+ pending->backend = InvalidBackendId;
+ pending->atCommit = false;
+ pending->nestLevel = GetCurrentTransactionNestLevel();
+ pending->next = pendingDeletes;
+ pendingDeletes = pending;
+ }
else
elog(PANIC, "smgr_redo: unknown op code %u", info);
}
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 993da56d43..37a15d31ee 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -50,6 +50,7 @@
#include "commands/defrem.h"
#include "commands/event_trigger.h"
#include "commands/policy.h"
+#include "commands/progress.h"
#include "commands/sequence.h"
#include "commands/tablecmds.h"
#include "commands/tablespace.h"
@@ -4917,6 +4918,170 @@ ATParseTransformCmd(List **wqueue, AlteredTableInfo *tab, Relation rel,
return newcmd;
}
+/*
+ * RelationChangePersistence: do in-place persistence change of a relation
+ */
+static void
+RelationChangePersistence(AlteredTableInfo *tab, char persistence,
+ LOCKMODE lockmode)
+{
+ Relation rel;
+ Relation classRel;
+ HeapTuple tuple,
+ newtuple;
+ Datum new_val[Natts_pg_class];
+ bool new_null[Natts_pg_class],
+ new_repl[Natts_pg_class];
+ int i;
+ List *relids;
+ ListCell *lc_oid;
+
+ Assert(tab->rewrite == AT_REWRITE_ALTER_PERSISTENCE);
+ Assert(lockmode == AccessExclusiveLock);
+
+ /*
+ * Under the following condition, we need to call ATRewriteTable, which
+ * cannot be false in the AT_REWRITE_ALTER_PERSISTENCE case.
+ */
+ Assert(tab->constraints == NULL && tab->partition_constraint == NULL &&
+ tab->newvals == NULL && !tab->verify_new_notnull);
+
+ rel = table_open(tab->relid, lockmode);
+
+ Assert(rel->rd_rel->relpersistence != persistence);
+
+ elog(DEBUG1, "perform im-place persistnce change");
+
+ RelationOpenSmgr(rel);
+
+ /*
+ * First we collect all relations that we need to change persistence.
+ */
+
+ /* Collect OIDs of indexes and toast relations */
+ relids = RelationGetIndexList(rel);
+ relids = lcons_oid(rel->rd_id, relids);
+
+ /* Add toast relation if any */
+ if (OidIsValid(rel->rd_rel->reltoastrelid))
+ {
+ List *toastidx;
+ Relation toastrel = table_open(rel->rd_rel->reltoastrelid, lockmode);
+
+ RelationOpenSmgr(toastrel);
+ relids = lappend_oid(relids, rel->rd_rel->reltoastrelid);
+ toastidx = RelationGetIndexList(toastrel);
+ relids = list_concat(relids, toastidx);
+ pfree(toastidx);
+ table_close(toastrel, NoLock);
+ }
+
+ table_close(rel, NoLock);
+
+ /* Make changes in storage */
+ classRel = table_open(RelationRelationId, RowExclusiveLock);
+
+ foreach (lc_oid, relids)
+ {
+ Oid reloid = lfirst_oid(lc_oid);
+ Relation r = relation_open(reloid, lockmode);
+
+ /*
+ * Some access methods do not accept in-place persistence change. For
+ * example, GiST uses page LSNs to figure out whether a block has
+ * changed, where UNLOGGED GiST indexes use fake LSNs that are
+ * incompatible with real LSNs used for LOGGED ones.
+ *
+ * XXXX: We don't bother allowing in-place persistence change for index
+ * methods other than btree for now.
+ */
+ if (r->rd_rel->relkind == RELKIND_INDEX &&
+ r->rd_rel->relam != BTREE_AM_OID)
+ {
+ int reindex_flags;
+
+ /* reindex doesn't allow concurrent use of the index */
+ table_close(r, NoLock);
+
+ reindex_flags =
+ REINDEX_REL_SUPPRESS_INDEX_USE |
+ REINDEX_REL_CHECK_CONSTRAINTS;
+
+ /* Set the same persistence with the parent relation. */
+ if (persistence == RELPERSISTENCE_UNLOGGED)
+ reindex_flags |= REINDEX_REL_FORCE_INDEXES_UNLOGGED;
+ else
+ reindex_flags |= REINDEX_REL_FORCE_INDEXES_PERMANENT;
+
+ reindex_index(reloid, reindex_flags, persistence, 0);
+
+ continue;
+ }
+
+ RelationOpenSmgr(r);
+
+ /* Create or drop init fork */
+ if (persistence == RELPERSISTENCE_UNLOGGED)
+ RelationCreateInitFork(r);
+ else
+ RelationDropInitFork(r);
+
+ /*
+ * When this relation gets WAL-logged, immediately sync all files but
+ * initfork to establish the initial state on storage. Buffers have
+ * already flushed out by RelationCreate(Drop)InitFork called just
+ * above. Initfork should have been synced as needed.
+ */
+ if (persistence == RELPERSISTENCE_PERMANENT)
+ {
+ for (i = 0 ; i < INIT_FORKNUM ; i++)
+ {
+ if (smgrexists(r->rd_smgr, i))
+ smgrimmedsync(r->rd_smgr, i);
+ }
+ }
+
+ /* Update catalog */
+ tuple = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(reloid));
+ if (!HeapTupleIsValid(tuple))
+ elog(ERROR, "cache lookup failed for relation %u", reloid);
+
+ memset(new_val, 0, sizeof(new_val));
+ memset(new_null, false, sizeof(new_null));
+ memset(new_repl, false, sizeof(new_repl));
+
+ new_val[Anum_pg_class_relpersistence - 1] = CharGetDatum(persistence);
+ new_null[Anum_pg_class_relpersistence - 1] = false;
+ new_repl[Anum_pg_class_relpersistence - 1] = true;
+
+ newtuple = heap_modify_tuple(tuple, RelationGetDescr(classRel),
+ new_val, new_null, new_repl);
+
+ CatalogTupleUpdate(classRel, &newtuple->t_self, newtuple);
+ heap_freetuple(newtuple);
+
+ /*
+ * While wal_level >= replica, switching to LOGGED requires the
+ * relation content to be WAL-logged to recover the table.
+ */
+ if (persistence == RELPERSISTENCE_PERMANENT && XLogIsNeeded())
+ {
+ ForkNumber fork;
+
+ for (fork = 0; fork < INIT_FORKNUM ; fork++)
+ {
+ if (smgrexists(r->rd_smgr, fork))
+ log_newpage_range(r, fork,
+ 0, smgrnblocks(r->rd_smgr, fork), false);
+ }
+ }
+
+ table_close(r, NoLock);
+ }
+
+ table_close(classRel, NoLock);
+}
+
/*
* ATRewriteTables: ALTER TABLE phase 3
*/
@@ -5037,45 +5202,52 @@ ATRewriteTables(AlterTableStmt *parsetree, List **wqueue, LOCKMODE lockmode,
tab->relid,
tab->rewrite);
- /*
- * Create transient table that will receive the modified data.
- *
- * Ensure it is marked correctly as logged or unlogged. We have
- * to do this here so that buffers for the new relfilenode will
- * have the right persistence set, and at the same time ensure
- * that the original filenode's buffers will get read in with the
- * correct setting (i.e. the original one). Otherwise a rollback
- * after the rewrite would possibly result with buffers for the
- * original filenode having the wrong persistence setting.
- *
- * NB: This relies on swap_relation_files() also swapping the
- * persistence. That wouldn't work for pg_class, but that can't be
- * unlogged anyway.
- */
- OIDNewHeap = make_new_heap(tab->relid, NewTableSpace, persistence,
- lockmode);
+ if (tab->rewrite == AT_REWRITE_ALTER_PERSISTENCE)
+ RelationChangePersistence(tab, persistence, lockmode);
+ else
+ {
+ /*
+ * Create transient table that will receive the modified data.
+ *
+ * Ensure it is marked correctly as logged or unlogged. We
+ * have to do this here so that buffers for the new relfilenode
+ * will have the right persistence set, and at the same time
+ * ensure that the original filenode's buffers will get read in
+ * with the correct setting (i.e. the original one). Otherwise
+ * a rollback after the rewrite would possibly result with
+ * buffers for the original filenode having the wrong
+ * persistence setting.
+ *
+ * NB: This relies on swap_relation_files() also swapping the
+ * persistence. That wouldn't work for pg_class, but that can't
+ * be unlogged anyway.
+ */
+ OIDNewHeap = make_new_heap(tab->relid, NewTableSpace, persistence,
+ lockmode);
- /*
- * Copy the heap data into the new table with the desired
- * modifications, and test the current data within the table
- * against new constraints generated by ALTER TABLE commands.
- */
- ATRewriteTable(tab, OIDNewHeap, lockmode);
+ /*
+ * Copy the heap data into the new table with the desired
+ * modifications, and test the current data within the table
+ * against new constraints generated by ALTER TABLE commands.
+ */
+ ATRewriteTable(tab, OIDNewHeap, lockmode);
- /*
- * Swap the physical files of the old and new heaps, then rebuild
- * indexes and discard the old heap. We can use RecentXmin for
- * the table's new relfrozenxid because we rewrote all the tuples
- * in ATRewriteTable, so no older Xid remains in the table. Also,
- * we never try to swap toast tables by content, since we have no
- * interest in letting this code work on system catalogs.
- */
- finish_heap_swap(tab->relid, OIDNewHeap,
- false, false, true,
- !OidIsValid(tab->newTableSpace),
- RecentXmin,
- ReadNextMultiXactId(),
- persistence);
+ /*
+ * Swap the physical files of the old and new heaps, then
+ * rebuild indexes and discard the old heap. We can use
+ * RecentXmin for the table's new relfrozenxid because we
+ * rewrote all the tuples in ATRewriteTable, so no older Xid
+ * remains in the table. Also, we never try to swap toast
+ * tables by content, since we have no interest in letting this
+ * code work on system catalogs.
+ */
+ finish_heap_swap(tab->relid, OIDNewHeap,
+ false, false, true,
+ !OidIsValid(tab->newTableSpace),
+ RecentXmin,
+ ReadNextMultiXactId(),
+ persistence);
+ }
}
else
{
diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c
index 71b5852224..b730b4417c 100644
--- a/src/backend/storage/buffer/bufmgr.c
+++ b/src/backend/storage/buffer/bufmgr.c
@@ -37,6 +37,7 @@
#include "access/xlog.h"
#include "catalog/catalog.h"
#include "catalog/storage.h"
+#include "catalog/storage_xlog.h"
#include "executor/instrument.h"
#include "lib/binaryheap.h"
#include "miscadmin.h"
@@ -3032,6 +3033,93 @@ DropRelFileNodeBuffers(RelFileNodeBackend rnode, ForkNumber *forkNum,
}
}
+/* ---------------------------------------------------------------------
+ * SetRelFileNodeBuffersPersistence
+ *
+ * This function changes the persistence of all buffer pages of a relation
+ * then writes all dirty pages of the relation out to disk when switching
+ * to PERMANENT. (or more accurately, out to kernel disk buffers),
+ * ensuring that the kernel has an up-to-date view of the relation.
+ *
+ * Generally, the caller should be holding AccessExclusiveLock on the
+ * target relation to ensure that no other backend is busy dirtying
+ * more blocks of the relation; the effects can't be expected to last
+ * after the lock is released.
+ *
+ * XXX currently it sequentially searches the buffer pool, should be
+ * changed to more clever ways of searching. This routine is not
+ * used in any performance-critical code paths, so it's not worth
+ * adding additional overhead to normal paths to make it go faster;
+ * but see also DropRelFileNodeBuffers.
+ * --------------------------------------------------------------------
+ */
+void
+SetRelationBuffersPersistence(SMgrRelation srel, bool permanent, bool isRedo)
+{
+ int i;
+ RelFileNodeBackend rnode = srel->smgr_rnode;
+
+ Assert (!RelFileNodeBackendIsTemp(rnode));
+
+ if (!isRedo)
+ log_smgrbufpersistence(&srel->smgr_rnode.node, permanent);
+
+ ResourceOwnerEnlargeBuffers(CurrentResourceOwner);
+
+ for (i = 0; i < NBuffers; i++)
+ {
+ BufferDesc *bufHdr = GetBufferDescriptor(i);
+ uint32 buf_state;
+
+ if (!RelFileNodeEquals(bufHdr->tag.rnode, rnode.node))
+ continue;
+
+ ReservePrivateRefCountEntry();
+
+ buf_state = LockBufHdr(bufHdr);
+
+ if (!RelFileNodeEquals(bufHdr->tag.rnode, rnode.node))
+ {
+ UnlockBufHdr(bufHdr, buf_state);
+ continue;
+ }
+
+ if (permanent)
+ {
+ /* Init fork is being dropped, drop buffers for it. */
+ if (bufHdr->tag.forkNum == INIT_FORKNUM)
+ {
+ InvalidateBuffer(bufHdr);
+ continue;
+ }
+
+ buf_state |= BM_PERMANENT;
+ pg_atomic_write_u32(&bufHdr->state, buf_state);
+
+ /* we flush this buffer when switching to PERMANENT */
+ if ((buf_state & (BM_VALID | BM_DIRTY)) == (BM_VALID | BM_DIRTY))
+ {
+ PinBuffer_Locked(bufHdr);
+ LWLockAcquire(BufferDescriptorGetContentLock(bufHdr),
+ LW_SHARED);
+ FlushBuffer(bufHdr, srel);
+ LWLockRelease(BufferDescriptorGetContentLock(bufHdr));
+ UnpinBuffer(bufHdr, true);
+ }
+ else
+ UnlockBufHdr(bufHdr, buf_state);
+ }
+ else
+ {
+ /* init fork is always BM_PERMANENT. See BufferAlloc */
+ if (bufHdr->tag.forkNum != INIT_FORKNUM)
+ buf_state &= ~BM_PERMANENT;
+
+ UnlockBufHdr(bufHdr, buf_state);
+ }
+ }
+}
+
/* ---------------------------------------------------------------------
* DropRelFileNodesAllBuffers
*
diff --git a/src/backend/storage/file/reinit.c b/src/backend/storage/file/reinit.c
index 40c758d789..b07709bc4f 100644
--- a/src/backend/storage/file/reinit.c
+++ b/src/backend/storage/file/reinit.c
@@ -16,29 +16,50 @@
#include <unistd.h>
+#include "access/xlog.h"
+#include "catalog/pg_tablespace_d.h"
#include "common/relpath.h"
+#include "storage/bufmgr.h"
#include "storage/copydir.h"
#include "storage/fd.h"
+#include "storage/md.h"
#include "storage/reinit.h"
+#include "storage/smgr.h"
#include "utils/hsearch.h"
#include "utils/memutils.h"
static void ResetUnloggedRelationsInTablespaceDir(const char *tsdirname,
- int op);
+ Oid tspid, int op);
static void ResetUnloggedRelationsInDbspaceDir(const char *dbspacedirname,
- int op);
+ Oid tspid, Oid dbid, int op);
typedef struct
{
Oid reloid; /* hash key */
-} unlogged_relation_entry;
+ bool has_init; /* has INIT fork */
+ bool dirty_init; /* needs to remove INIT fork */
+ bool dirty_all; /* needs to remove all forks */
+} relfile_entry;
/*
- * Reset unlogged relations from before the last restart.
+ * Clean up and reset relation files from before the last restart.
*
- * If op includes UNLOGGED_RELATION_CLEANUP, we remove all forks of any
- * relation with an "init" fork, except for the "init" fork itself.
+ * If op includes UNLOGGED_RELATION_CLEANUP, we perform different operations
+ * depending on the existence of the "cleanup" forks.
*
+ * If CLEANUP_FORKNUM (clup) is present, we remove the init fork of the same
+ * relation along with the clup fork.
+ *
+ * If CLEANUP2_FORKNUM (cln2) is present we remove the whole relation along
+ * with the cln2 fork.
+ *
+ * Otherwise, if the "init" fork is found. we remove all forks of any relation
+ * with the "init" fork, except for the "init" fork itself.
+ *
+ *
+ * If op includes UNLOGGED_RELATION_DROP_BUFFER, we drop all buffers for all
+ * relations that have the "cleanup" and/or the "init" forks.
+ *
* If op includes UNLOGGED_RELATION_INIT, we copy the "init" fork to the main
* fork.
*/
@@ -68,7 +89,7 @@ ResetUnloggedRelations(int op)
/*
* First process unlogged files in pg_default ($PGDATA/base)
*/
- ResetUnloggedRelationsInTablespaceDir("base", op);
+ ResetUnloggedRelationsInTablespaceDir("base", DEFAULTTABLESPACE_OID, op);
/*
* Cycle through directories for all non-default tablespaces.
@@ -77,13 +98,19 @@ ResetUnloggedRelations(int op)
while ((spc_de = ReadDir(spc_dir, "pg_tblspc")) != NULL)
{
+ Oid tspid;
+
if (strcmp(spc_de->d_name, ".") == 0 ||
strcmp(spc_de->d_name, "..") == 0)
continue;
snprintf(temp_path, sizeof(temp_path), "pg_tblspc/%s/%s",
spc_de->d_name, TABLESPACE_VERSION_DIRECTORY);
- ResetUnloggedRelationsInTablespaceDir(temp_path, op);
+
+ tspid = atooid(spc_de->d_name);
+ Assert(tspid != 0);
+
+ ResetUnloggedRelationsInTablespaceDir(temp_path, tspid, op);
}
FreeDir(spc_dir);
@@ -99,7 +126,8 @@ ResetUnloggedRelations(int op)
* Process one tablespace directory for ResetUnloggedRelations
*/
static void
-ResetUnloggedRelationsInTablespaceDir(const char *tsdirname, int op)
+ResetUnloggedRelationsInTablespaceDir(const char *tsdirname,
+ Oid tspid, int op)
{
DIR *ts_dir;
struct dirent *de;
@@ -126,6 +154,8 @@ ResetUnloggedRelationsInTablespaceDir(const char *tsdirname, int op)
while ((de = ReadDir(ts_dir, tsdirname)) != NULL)
{
+ Oid dbid;
+
/*
* We're only interested in the per-database directories, which have
* numeric names. Note that this code will also (properly) ignore "."
@@ -136,7 +166,10 @@ ResetUnloggedRelationsInTablespaceDir(const char *tsdirname, int op)
snprintf(dbspace_path, sizeof(dbspace_path), "%s/%s",
tsdirname, de->d_name);
- ResetUnloggedRelationsInDbspaceDir(dbspace_path, op);
+ dbid = atooid(de->d_name);
+ Assert(dbid != 0);
+
+ ResetUnloggedRelationsInDbspaceDir(dbspace_path, tspid, dbid, op);
}
FreeDir(ts_dir);
@@ -146,125 +179,232 @@ ResetUnloggedRelationsInTablespaceDir(const char *tsdirname, int op)
* Process one per-dbspace directory for ResetUnloggedRelations
*/
static void
-ResetUnloggedRelationsInDbspaceDir(const char *dbspacedirname, int op)
+ResetUnloggedRelationsInDbspaceDir(const char *dbspacedirname,
+ Oid tspid, Oid dbid, int op)
{
DIR *dbspace_dir;
struct dirent *de;
char rm_path[MAXPGPATH * 2];
+ HTAB *hash;
+ HASHCTL ctl;
/* Caller must specify at least one operation. */
- Assert((op & (UNLOGGED_RELATION_CLEANUP | UNLOGGED_RELATION_INIT)) != 0);
+ Assert((op & (UNLOGGED_RELATION_CLEANUP |
+ UNLOGGED_RELATION_DROP_BUFFER |
+ UNLOGGED_RELATION_INIT)) != 0);
/*
* Cleanup is a two-pass operation. First, we go through and identify all
* the files with init forks. Then, we go through again and nuke
* everything with the same OID except the init fork.
*/
+
+ /*
+ * It's possible that someone could create a ton of unlogged relations
+ * in the same database & tablespace, so we'd better use a hash table
+ * rather than an array or linked list to keep track of which files
+ * need to be reset. Otherwise, this cleanup operation would be
+ * O(n^2).
+ */
+ memset(&ctl, 0, sizeof(ctl));
+ ctl.keysize = sizeof(Oid);
+ ctl.entrysize = sizeof(relfile_entry);
+ hash = hash_create("relfilenode cleanup hash",
+ 32, &ctl, HASH_ELEM | HASH_BLOBS);
+
+ /* Collect INIT and CLEANUP forks in the directory. */
+ dbspace_dir = AllocateDir(dbspacedirname);
+ while ((de = ReadDir(dbspace_dir, dbspacedirname)) != NULL)
+ {
+ int oidchars;
+ ForkNumber forkNum;
+
+ /* Skip anything that doesn't look like a relation data file. */
+ if (!parse_filename_for_nontemp_relation(de->d_name, &oidchars,
+ &forkNum))
+ continue;
+
+ if (forkNum == INIT_FORKNUM ||
+ forkNum == CLEANUP_FORKNUM || forkNum == CLEANUP2_FORKNUM)
+ {
+ Oid key;
+ relfile_entry *ent;
+ bool found;
+
+ /*
+ * Record the relfilenode information. If it has the CLEANUP fork,
+ * the relfilenode is in dirty state, where clean up is needed.
+ */
+ key = atooid(de->d_name);
+ ent = hash_search(hash, &key, HASH_ENTER, &found);
+
+ if (!found)
+ {
+ ent->has_init = false;
+ ent->dirty_init = false;
+ ent->dirty_all = false;
+ }
+
+ if (forkNum == CLEANUP_FORKNUM)
+ ent->dirty_init = true;
+ else if (forkNum == CLEANUP2_FORKNUM)
+ ent->dirty_all = true;
+ else
+ {
+ Assert(forkNum == INIT_FORKNUM);
+ ent->has_init = true;
+ }
+ }
+ }
+
+ /* Done with the first pass. */
+ FreeDir(dbspace_dir);
+
+ /* nothing to do if we don't have init nor cleanup forks */
+ if (hash_get_num_entries(hash) < 1)
+ {
+ hash_destroy(hash);
+ return;
+ }
+
+ if ((op & UNLOGGED_RELATION_DROP_BUFFER) != 0)
+ {
+ /*
+ * When we come here after recovery, smgr object for this file might
+ * have been created. In that case we need to drop all buffers then the
+ * smgr object before initializing the unlogged relation. This is safe
+ * as far as no other backends have accessed the relation before
+ * starting archive recovery.
+ */
+ HASH_SEQ_STATUS status;
+ relfile_entry *ent;
+ SMgrRelation *srels = palloc(sizeof(SMgrRelation) * 8);
+ int maxrels = 8;
+ int nrels = 0;
+ RelFileNodeBackend *rnodes;
+ int i;
+
+ Assert(!HotStandbyActive());
+
+ hash_seq_init(&status, hash);
+ while((ent = (relfile_entry *) hash_seq_search(&status)) != NULL)
+ {
+ RelFileNodeBackend rel;
+
+ /*
+ * The relation is persistent and stays remain persistent. Don't
+ * drop the buffers for this relation.
+ */
+ if (ent->has_init && ent->dirty_init)
+ continue;
+
+ if (maxrels <= nrels)
+ {
+ maxrels *= 2;
+ srels = repalloc(srels, sizeof(SMgrRelation) * maxrels);
+ }
+
+ rel.backend = InvalidBackendId;
+ rel.node.spcNode = tspid;
+ rel.node.dbNode = dbid;
+ rel.node.relNode = ent->reloid;
+
+ srels[nrels++] = smgropen(rel.node, InvalidBackendId);
+ }
+
+ rnodes = palloc(sizeof(RelFileNodeBackend) * nrels);
+
+ for (i = 0 ; i < nrels ; i++)
+ rnodes[i] = srels[i]->smgr_rnode;
+
+ DropRelFileNodesAllBuffers(rnodes, nrels);
+
+ for (i = 0 ; i < nrels ; i++)
+ smgrclose(srels[i]);
+ }
+
+ /*
+ * Now, make a second pass and remove anything that matches.
+ */
if ((op & UNLOGGED_RELATION_CLEANUP) != 0)
{
- HTAB *hash;
- HASHCTL ctl;
-
- /*
- * It's possible that someone could create a ton of unlogged relations
- * in the same database & tablespace, so we'd better use a hash table
- * rather than an array or linked list to keep track of which files
- * need to be reset. Otherwise, this cleanup operation would be
- * O(n^2).
- */
- ctl.keysize = sizeof(Oid);
- ctl.entrysize = sizeof(unlogged_relation_entry);
- ctl.hcxt = CurrentMemoryContext;
- hash = hash_create("unlogged relation OIDs", 32, &ctl,
- HASH_ELEM | HASH_BLOBS | HASH_CONTEXT);
-
- /* Scan the directory. */
- dbspace_dir = AllocateDir(dbspacedirname);
- while ((de = ReadDir(dbspace_dir, dbspacedirname)) != NULL)
- {
- ForkNumber forkNum;
- int oidchars;
- unlogged_relation_entry ent;
-
- /* Skip anything that doesn't look like a relation data file. */
- if (!parse_filename_for_nontemp_relation(de->d_name, &oidchars,
- &forkNum))
- continue;
-
- /* Also skip it unless this is the init fork. */
- if (forkNum != INIT_FORKNUM)
- continue;
-
- /*
- * Put the OID portion of the name into the hash table, if it
- * isn't already.
- */
- ent.reloid = atooid(de->d_name);
- (void) hash_search(hash, &ent, HASH_ENTER, NULL);
- }
-
- /* Done with the first pass. */
- FreeDir(dbspace_dir);
-
- /*
- * If we didn't find any init forks, there's no point in continuing;
- * we can bail out now.
- */
- if (hash_get_num_entries(hash) == 0)
- {
- hash_destroy(hash);
- return;
- }
-
- /*
- * Now, make a second pass and remove anything that matches.
- */
dbspace_dir = AllocateDir(dbspacedirname);
while ((de = ReadDir(dbspace_dir, dbspacedirname)) != NULL)
{
- ForkNumber forkNum;
- int oidchars;
- unlogged_relation_entry ent;
+ ForkNumber forkNum;
+ int oidchars;
+ Oid key;
+ relfile_entry *ent;
+ RelFileNodeBackend rel;
/* Skip anything that doesn't look like a relation data file. */
if (!parse_filename_for_nontemp_relation(de->d_name, &oidchars,
&forkNum))
continue;
- /* We never remove the init fork. */
- if (forkNum == INIT_FORKNUM)
- continue;
-
/*
* See whether the OID portion of the name shows up in the hash
* table. If so, nuke it!
*/
- ent.reloid = atooid(de->d_name);
- if (hash_search(hash, &ent, HASH_FIND, NULL))
+ key = atooid(de->d_name);
+ ent = hash_search(hash, &key, HASH_FIND, NULL);
+
+ if (!ent)
+ continue;
+
+ if (!ent->dirty_all)
{
- snprintf(rm_path, sizeof(rm_path), "%s/%s",
- dbspacedirname, de->d_name);
- if (unlink(rm_path) < 0)
- ereport(ERROR,
- (errcode_for_file_access(),
- errmsg("could not remove file \"%s\": %m",
- rm_path)));
+ /* clean permanent relations don't need cleanup */
+ if (!ent->has_init)
+ continue;
+
+ if (ent->dirty_init)
+ {
+ /*
+ * The crashed trasaction did SET UNLOGGED. This relation
+ * is restored to a LOGGED relation.
+ */
+ if (forkNum != INIT_FORKNUM && forkNum != CLEANUP_FORKNUM)
+ continue;
+ }
else
- elog(DEBUG2, "unlinked file \"%s\"", rm_path);
+ {
+ /*
+ * we don't remove the INIT fork of a non-dirty
+ * relfilenode
+ */
+ if (forkNum == INIT_FORKNUM)
+ continue;
+ }
}
+
+ /* so, nuke it! */
+ snprintf(rm_path, sizeof(rm_path), "%s/%s",
+ dbspacedirname, de->d_name);
+ if (unlink(rm_path) < 0)
+ ereport(ERROR,
+ (errcode_for_file_access(),
+ errmsg("could not remove file \"%s\": %m",
+ rm_path)));
+
+ rel.backend = InvalidBackendId;
+ rel.node.spcNode = tspid;
+ rel.node.dbNode = dbid;
+ rel.node.relNode = atooid(de->d_name);
+
+ ForgetRelationForkSyncRequests(rel, forkNum);
}
/* Cleanup is complete. */
FreeDir(dbspace_dir);
- hash_destroy(hash);
}
+ hash_destroy(hash);
+ hash = NULL;
+
/*
* Initialization happens after cleanup is complete: we copy each init
- * fork file to the corresponding main fork file. Note that if we are
- * asked to do both cleanup and init, we may never get here: if the
- * cleanup code determines that there are no init forks in this dbspace,
- * it will return before we get to this point.
+ * fork file to the corresponding main fork file.
*/
if ((op & UNLOGGED_RELATION_INIT) != 0)
{
diff --git a/src/backend/storage/smgr/md.c b/src/backend/storage/smgr/md.c
index 0643d714fb..6b37195c52 100644
--- a/src/backend/storage/smgr/md.c
+++ b/src/backend/storage/smgr/md.c
@@ -338,8 +338,10 @@ mdunlinkfork(RelFileNodeBackend rnode, ForkNumber forkNum, bool isRedo)
if (ret == 0 || errno != ENOENT)
{
ret = unlink(path);
+
+ /* failure of removing cleanup fork leads to a data loss. */
if (ret < 0 && errno != ENOENT)
- ereport(WARNING,
+ ereport((forkNum != CLEANUP_FORKNUM ? WARNING : ERROR),
(errcode_for_file_access(),
errmsg("could not remove file \"%s\": %m", path)));
}
@@ -1024,6 +1026,15 @@ register_forget_request(RelFileNodeBackend rnode, ForkNumber forknum,
RegisterSyncRequest(&tag, SYNC_FORGET_REQUEST, true /* retryOnError */ );
}
+/*
+ * ForgetRelationForkSyncRequests -- forget any fsyncs and unlinks for a fork
+ */
+void
+ForgetRelationForkSyncRequests(RelFileNodeBackend rnode, ForkNumber forknum)
+{
+ register_forget_request(rnode, forknum, 0);
+}
+
/*
* ForgetDatabaseSyncRequests -- forget any fsyncs and unlinks for a DB
*/
diff --git a/src/backend/storage/smgr/smgr.c b/src/backend/storage/smgr/smgr.c
index 0f31ff3822..4102d3d59c 100644
--- a/src/backend/storage/smgr/smgr.c
+++ b/src/backend/storage/smgr/smgr.c
@@ -644,6 +644,12 @@ smgrimmedsync(SMgrRelation reln, ForkNumber forknum)
smgrsw[reln->smgr_which].smgr_immedsync(reln, forknum);
}
+void
+smgrunlink(SMgrRelation reln, ForkNumber forknum, bool isRedo)
+{
+ smgrsw[reln->smgr_which].smgr_unlink(reln->smgr_rnode, forknum, isRedo);
+}
+
/*
* AtEOXact_SMgr
*
diff --git a/src/common/relpath.c b/src/common/relpath.c
index 1f5c426ec0..479dcc248e 100644
--- a/src/common/relpath.c
+++ b/src/common/relpath.c
@@ -34,7 +34,9 @@ const char *const forkNames[] = {
"main", /* MAIN_FORKNUM */
"fsm", /* FSM_FORKNUM */
"vm", /* VISIBILITYMAP_FORKNUM */
- "init" /* INIT_FORKNUM */
+ "init", /* INIT_FORKNUM */
+ "clup", /* CLEANUP_FORKNUM */
+ "cln2" /* CLEANUP2_FORKNUM */
};
StaticAssertDecl(lengthof(forkNames) == (MAX_FORKNUM + 1),
diff --git a/src/include/catalog/storage.h b/src/include/catalog/storage.h
index 0ab32b44e9..382623159c 100644
--- a/src/include/catalog/storage.h
+++ b/src/include/catalog/storage.h
@@ -23,6 +23,8 @@
extern int wal_skip_threshold;
extern SMgrRelation RelationCreateStorage(RelFileNode rnode, char relpersistence);
+extern void RelationCreateInitFork(Relation rel);
+extern void RelationDropInitFork(Relation rel);
extern void RelationDropStorage(Relation rel);
extern void RelationPreserveStorage(RelFileNode rnode, bool atCommit);
extern void RelationPreTruncate(Relation rel);
diff --git a/src/include/catalog/storage_xlog.h b/src/include/catalog/storage_xlog.h
index f0814f1458..0fd0832a8b 100644
--- a/src/include/catalog/storage_xlog.h
+++ b/src/include/catalog/storage_xlog.h
@@ -22,13 +22,17 @@
/*
* Declarations for smgr-related XLOG records
*
- * Note: we log file creation and truncation here, but logging of deletion
- * actions is handled by xact.c, because it is part of transaction commit.
+ * Note: we log file creation, truncation, deletion and persistence change
+ * here. logging of deletion actions is mainly handled by xact.c, because it is
+ * part of transaction commit, but we log deletions happens outside of a
+ * transaction.
*/
/* XLOG gives us high 4 bits */
#define XLOG_SMGR_CREATE 0x10
#define XLOG_SMGR_TRUNCATE 0x20
+#define XLOG_SMGR_UNLINK 0x30
+#define XLOG_SMGR_BUFPERSISTENCE 0x40
typedef struct xl_smgr_create
{
@@ -36,6 +40,18 @@ typedef struct xl_smgr_create
ForkNumber forkNum;
} xl_smgr_create;
+typedef struct xl_smgr_unlink
+{
+ RelFileNode rnode;
+ ForkNumber forkNum;
+} xl_smgr_unlink;
+
+typedef struct xl_smgr_bufpersistence
+{
+ RelFileNode rnode;
+ bool persistence;
+} xl_smgr_bufpersistence;
+
/* flags for xl_smgr_truncate */
#define SMGR_TRUNCATE_HEAP 0x0001
#define SMGR_TRUNCATE_VM 0x0002
@@ -51,6 +67,8 @@ typedef struct xl_smgr_truncate
} xl_smgr_truncate;
extern void log_smgrcreate(const RelFileNode *rnode, ForkNumber forkNum);
+extern void log_smgrunlink(const RelFileNode *rnode, ForkNumber forkNum);
+extern void log_smgrbufpersistence(const RelFileNode *rnode, bool persistence);
extern void smgr_redo(XLogReaderState *record);
extern void smgr_desc(StringInfo buf, XLogReaderState *record);
diff --git a/src/include/common/relpath.h b/src/include/common/relpath.h
index a44be11ca0..040070aa2b 100644
--- a/src/include/common/relpath.h
+++ b/src/include/common/relpath.h
@@ -43,7 +43,9 @@ typedef enum ForkNumber
MAIN_FORKNUM = 0,
FSM_FORKNUM,
VISIBILITYMAP_FORKNUM,
- INIT_FORKNUM
+ INIT_FORKNUM,
+ CLEANUP_FORKNUM,
+ CLEANUP2_FORKNUM
/*
* NOTE: if you add a new fork, change MAX_FORKNUM and possibly
@@ -52,7 +54,7 @@ typedef enum ForkNumber
*/
} ForkNumber;
-#define MAX_FORKNUM INIT_FORKNUM
+#define MAX_FORKNUM CLEANUP2_FORKNUM
#define FORKNAMECHARS 4 /* max chars for a fork name */
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index ff6cd0fc54..d9752a8317 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -205,6 +205,8 @@ extern void FlushRelationsAllBuffers(struct SMgrRelationData **smgrs, int nrels)
extern void FlushDatabaseBuffers(Oid dbid);
extern void DropRelFileNodeBuffers(RelFileNodeBackend rnode, ForkNumber *forkNum,
int nforks, BlockNumber *firstDelBlock);
+extern void SetRelationBuffersPersistence(struct SMgrRelationData *srel,
+ bool permanent, bool isRedo);
extern void DropRelFileNodesAllBuffers(RelFileNodeBackend *rnodes, int nnodes);
extern void DropDatabaseBuffers(Oid dbid);
diff --git a/src/include/storage/md.h b/src/include/storage/md.h
index 752b440864..3cbbbf2edd 100644
--- a/src/include/storage/md.h
+++ b/src/include/storage/md.h
@@ -41,6 +41,8 @@ extern void mdtruncate(SMgrRelation reln, ForkNumber forknum,
BlockNumber nblocks);
extern void mdimmedsync(SMgrRelation reln, ForkNumber forknum);
+extern void ForgetRelationForkSyncRequests(RelFileNodeBackend rnode,
+ ForkNumber forknum);
extern void ForgetDatabaseSyncRequests(Oid dbid);
extern void DropRelationFiles(RelFileNode *delrels, int ndelrels, bool isRedo);
diff --git a/src/include/storage/reinit.h b/src/include/storage/reinit.h
index fad1e5c473..b969ba8e86 100644
--- a/src/include/storage/reinit.h
+++ b/src/include/storage/reinit.h
@@ -23,6 +23,7 @@ extern bool parse_filename_for_nontemp_relation(const char *name,
int *oidchars, ForkNumber *fork);
#define UNLOGGED_RELATION_CLEANUP 0x0001
-#define UNLOGGED_RELATION_INIT 0x0002
+#define UNLOGGED_RELATION_DROP_BUFFER 0x0002
+#define UNLOGGED_RELATION_INIT 0x0004
#endif /* REINIT_H */
diff --git a/src/include/storage/smgr.h b/src/include/storage/smgr.h
index ebf4a199dc..8be17d9afc 100644
--- a/src/include/storage/smgr.h
+++ b/src/include/storage/smgr.h
@@ -86,6 +86,7 @@ extern void smgrclose(SMgrRelation reln);
extern void smgrcloseall(void);
extern void smgrclosenode(RelFileNodeBackend rnode);
extern void smgrcreate(SMgrRelation reln, ForkNumber forknum, bool isRedo);
+extern void smgrunlink(SMgrRelation reln, ForkNumber forknum, bool isRedo);
extern void smgrdosyncall(SMgrRelation *rels, int nrels);
extern void smgrdounlinkall(SMgrRelation *rels, int nrels, bool isRedo);
extern void smgrextend(SMgrRelation reln, ForkNumber forknum,
--
2.27.0
----Next_Part(Tue_Jan_12_18_58_08_2021_481)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
filename="v4-0002-New-command-ALTER-TABLE-ALL-IN-TABLESPACE-SET-LOG.patch"
^ permalink raw reply [nested|flat] 3+ messages in thread
* WaitEventSet resource leakage
@ 2023-03-09 18:51 Tom Lane <[email protected]>
2023-11-15 22:48 ` Re: WaitEventSet resource leakage Heikki Linnakangas <[email protected]>
0 siblings, 1 reply; 3+ messages in thread
From: Tom Lane @ 2023-03-09 18:51 UTC (permalink / raw)
To: [email protected]
In [1] I wrote:
> PG Bug reporting form <[email protected]> writes:
>> The following script:
>> [ leaks a file descriptor per error ]
>
> Yeah, at least on platforms where WaitEventSets own kernel file
> descriptors. I don't think it's postgres_fdw's fault though,
> but that of ExecAppendAsyncEventWait, which is ignoring the
> possibility of failing partway through. It looks like it'd be
> sufficient to add a PG_CATCH or PG_FINALLY block there to make
> sure the WaitEventSet is disposed of properly --- fortunately,
> it doesn't need to have any longer lifespan than that one
> function.
After further thought that seems like a pretty ad-hoc solution.
We probably can do no better in the back branches, but shouldn't
we start treating WaitEventSets as ResourceOwner-managed resources?
Otherwise, transient WaitEventSets are going to be a permanent
source of headaches.
regards, tom lane
[1] https://www.postgresql.org/message-id/423731.1678381075%40sss.pgh.pa.us
^ permalink raw reply [nested|flat] 3+ messages in thread
* Re: WaitEventSet resource leakage
2023-03-09 18:51 WaitEventSet resource leakage Tom Lane <[email protected]>
@ 2023-11-15 22:48 ` Heikki Linnakangas <[email protected]>
0 siblings, 0 replies; 3+ messages in thread
From: Heikki Linnakangas @ 2023-11-15 22:48 UTC (permalink / raw)
To: Tom Lane <[email protected]>; [email protected]; Alexander Lakhin <[email protected]>
(Alexander just reminded me of this off-list)
On 09/03/2023 20:51, Tom Lane wrote:
> In [1] I wrote:
>
>> PG Bug reporting form <[email protected]> writes:
>>> The following script:
>>> [ leaks a file descriptor per error ]
>>
>> Yeah, at least on platforms where WaitEventSets own kernel file
>> descriptors. I don't think it's postgres_fdw's fault though,
>> but that of ExecAppendAsyncEventWait, which is ignoring the
>> possibility of failing partway through. It looks like it'd be
>> sufficient to add a PG_CATCH or PG_FINALLY block there to make
>> sure the WaitEventSet is disposed of properly --- fortunately,
>> it doesn't need to have any longer lifespan than that one
>> function.
Here's a patch to do that. For back branches.
> After further thought that seems like a pretty ad-hoc solution.
> We probably can do no better in the back branches, but shouldn't
> we start treating WaitEventSets as ResourceOwner-managed resources?
> Otherwise, transient WaitEventSets are going to be a permanent
> source of headaches.
Agreed. The current signature of CurrentWaitEventSet is:
WaitEventSet *
CreateWaitEventSet(MemoryContext context, int nevents)
Passing MemoryContext makes little sense when the WaitEventSet also
holds file descriptors. With anything other than TopMemoryContext, you
need to arrange for proper cleanup with PG_TRY-PG_CATCH or by avoiding
ereport() calls. And once you've arrange for cleanup, the memory context
doesn't matter much anymore.
Let's change it so that it's always allocated in TopMemoryContext, but
pass a ResourceOwner instead:
WaitEventSet *
CreateWaitEventSet(ResourceOwner owner, int nevents)
And use owner == NULL to mean session lifetime.
--
Heikki Linnakangas
Neon (https://neon.tech)
Attachments:
[text/x-patch] v1-0001-Fix-resource-leak-when-a-FDW-s-ForeignAsyncReques.patch (5.7K, ../../[email protected]/2-v1-0001-Fix-resource-leak-when-a-FDW-s-ForeignAsyncReques.patch)
download | inline diff:
From b9ea609855b838369cddb33e4045ac91603dd726 Mon Sep 17 00:00:00 2001
From: Heikki Linnakangas <[email protected]>
Date: Wed, 15 Nov 2023 23:44:56 +0100
Subject: [PATCH v1 1/1] Fix resource leak when a FDW's ForeignAsyncRequest
function fails
If an error is thrown after calling CreateWaitEventSet(), the memory
of a WaitEventSet is free'd as it's allocated in the short-lived
memory context, but the file descriptor (on epoll- or kqueue-based
systems) or handles (on Windows) that it contains are leaked. Use
PG_TRY-FINALLY to ensure it gets freed.
In the passing, fix misleading comment on what the 'nevents' argument
to WaitEventSetWait means.
The added test doesn't check for leaking resources, so it passed even
before this commit. But at least it covers the code path.
Report by Alexander Lakhin, analysis and suggestion for the fix by
Tom Lane.
Discussion: https://www.postgresql.org/message-id/[email protected]
Discussion: https://www.postgresql.org/message-id/[email protected]
---
.../postgres_fdw/expected/postgres_fdw.out | 7 ++
contrib/postgres_fdw/sql/postgres_fdw.sql | 6 ++
src/backend/executor/nodeAppend.c | 66 +++++++++++--------
3 files changed, 50 insertions(+), 29 deletions(-)
diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out
index 64bcc66b8d..22cae37a1e 100644
--- a/contrib/postgres_fdw/expected/postgres_fdw.out
+++ b/contrib/postgres_fdw/expected/postgres_fdw.out
@@ -10809,6 +10809,13 @@ SELECT * FROM result_tbl ORDER BY a;
(2 rows)
DELETE FROM result_tbl;
+-- Test error handling, if accessing one of the foreign partitions errors out
+CREATE FOREIGN TABLE async_p_broken PARTITION OF async_pt FOR VALUES FROM (10000) TO (10001)
+ SERVER loopback OPTIONS (table_name 'non_existent_table');
+SELECT * FROM async_pt;
+ERROR: relation "public.non_existent_table" does not exist
+CONTEXT: remote SQL command: SELECT a, b, c FROM public.non_existent_table
+DROP FOREIGN TABLE async_p_broken;
-- Check case where multiple partitions use the same connection
CREATE TABLE base_tbl3 (a int, b int, c text);
CREATE FOREIGN TABLE async_p3 PARTITION OF async_pt FOR VALUES FROM (3000) TO (4000)
diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql
index 2d14eeadb5..075da4ff86 100644
--- a/contrib/postgres_fdw/sql/postgres_fdw.sql
+++ b/contrib/postgres_fdw/sql/postgres_fdw.sql
@@ -3607,6 +3607,12 @@ INSERT INTO result_tbl SELECT a, b, 'AAA' || c FROM async_pt WHERE b === 505;
SELECT * FROM result_tbl ORDER BY a;
DELETE FROM result_tbl;
+-- Test error handling, if accessing one of the foreign partitions errors out
+CREATE FOREIGN TABLE async_p_broken PARTITION OF async_pt FOR VALUES FROM (10000) TO (10001)
+ SERVER loopback OPTIONS (table_name 'non_existent_table');
+SELECT * FROM async_pt;
+DROP FOREIGN TABLE async_p_broken;
+
-- Check case where multiple partitions use the same connection
CREATE TABLE base_tbl3 (a int, b int, c text);
CREATE FOREIGN TABLE async_p3 PARTITION OF async_pt FOR VALUES FROM (3000) TO (4000)
diff --git a/src/backend/executor/nodeAppend.c b/src/backend/executor/nodeAppend.c
index 609df6b9e6..99818d3ebc 100644
--- a/src/backend/executor/nodeAppend.c
+++ b/src/backend/executor/nodeAppend.c
@@ -1025,43 +1025,51 @@ ExecAppendAsyncEventWait(AppendState *node)
/* We should never be called when there are no valid async subplans. */
Assert(node->as_nasyncremain > 0);
+ Assert(node->as_eventset == NULL);
node->as_eventset = CreateWaitEventSet(CurrentMemoryContext, nevents);
- AddWaitEventToSet(node->as_eventset, WL_EXIT_ON_PM_DEATH, PGINVALID_SOCKET,
- NULL, NULL);
-
- /* Give each waiting subplan a chance to add an event. */
- i = -1;
- while ((i = bms_next_member(node->as_asyncplans, i)) >= 0)
+ PG_TRY();
{
- AsyncRequest *areq = node->as_asyncrequests[i];
+ AddWaitEventToSet(node->as_eventset, WL_EXIT_ON_PM_DEATH, PGINVALID_SOCKET,
+ NULL, NULL);
- if (areq->callback_pending)
- ExecAsyncConfigureWait(areq);
- }
+ /* Give each waiting subplan a chance to add an event. */
+ i = -1;
+ while ((i = bms_next_member(node->as_asyncplans, i)) >= 0)
+ {
+ AsyncRequest *areq = node->as_asyncrequests[i];
- /*
- * No need for further processing if there are no configured events other
- * than the postmaster death event.
- */
- if (GetNumRegisteredWaitEvents(node->as_eventset) == 1)
+ if (areq->callback_pending)
+ ExecAsyncConfigureWait(areq);
+ }
+
+ /*
+ * No need for further processing if there are no configured events
+ * other than the postmaster death event.
+ */
+ if (GetNumRegisteredWaitEvents(node->as_eventset) == 1)
+ {
+ FreeWaitEventSet(node->as_eventset);
+ node->as_eventset = NULL;
+ return;
+ }
+
+ /* Return at most EVENT_BUFFER_SIZE events in one call. */
+ if (nevents > EVENT_BUFFER_SIZE)
+ nevents = EVENT_BUFFER_SIZE;
+
+ /*
+ * If the timeout is -1, wait until at least one event occurs. If the
+ * timeout is 0, poll for events, but do not wait at all.
+ */
+ noccurred = WaitEventSetWait(node->as_eventset, timeout, occurred_event,
+ nevents, WAIT_EVENT_APPEND_READY);
+ }
+ PG_FINALLY();
{
FreeWaitEventSet(node->as_eventset);
node->as_eventset = NULL;
- return;
}
-
- /* We wait on at most EVENT_BUFFER_SIZE events. */
- if (nevents > EVENT_BUFFER_SIZE)
- nevents = EVENT_BUFFER_SIZE;
-
- /*
- * If the timeout is -1, wait until at least one event occurs. If the
- * timeout is 0, poll for events, but do not wait at all.
- */
- noccurred = WaitEventSetWait(node->as_eventset, timeout, occurred_event,
- nevents, WAIT_EVENT_APPEND_READY);
- FreeWaitEventSet(node->as_eventset);
- node->as_eventset = NULL;
+ PG_END_TRY();
if (noccurred == 0)
return;
--
2.39.2
^ permalink raw reply [nested|flat] 3+ messages in thread
end of thread, other threads:[~2023-11-15 22:48 UTC | newest]
Thread overview: 3+ messages (download: mbox mbox.gz follow: Atom feed)
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2020-11-11 12:51 [PATCH v4 1/2] In-place table persistence change Kyotaro Horiguchi <[email protected]>
2023-03-09 18:51 WaitEventSet resource leakage Tom Lane <[email protected]>
2023-11-15 22:48 ` Re: WaitEventSet resource leakage Heikki Linnakangas <[email protected]>
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