* twophase.c
* Two-phase commit support functions.
*
- * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2014, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/access/transam/twophase.c,v 1.36 2007/09/21 16:32:19 tgl Exp $
+ * src/backend/access/transam/twophase.c
*
* NOTES
* Each global transaction is associated with a global transaction
* GIDs and aborts the transaction if there already is a global
* transaction in prepared state with the same GID.
*
- * A global transaction (gxact) also has a dummy PGPROC that is entered
- * into the ProcArray array; this is what keeps the XID considered
- * running by TransactionIdIsInProgress. It is also convenient as a
- * PGPROC to hook the gxact's locks to.
+ * A global transaction (gxact) also has dummy PGXACT and PGPROC; this is
+ * what keeps the XID considered running by TransactionIdIsInProgress.
+ * It is also convenient as a PGPROC to hook the gxact's locks to.
*
* In order to survive crashes and shutdowns, all prepared
* transactions must be stored in permanent storage. This includes
#include <time.h>
#include <unistd.h>
-#include "access/heapam.h"
+#include "access/htup_details.h"
#include "access/subtrans.h"
#include "access/transam.h"
#include "access/twophase.h"
#include "access/twophase_rmgr.h"
#include "access/xact.h"
+#include "access/xlog.h"
+#include "access/xlogutils.h"
#include "catalog/pg_type.h"
+#include "catalog/storage.h"
#include "funcapi.h"
#include "miscadmin.h"
+#include "pg_trace.h"
#include "pgstat.h"
+#include "replication/walsender.h"
+#include "replication/syncrep.h"
#include "storage/fd.h"
+#include "storage/predicate.h"
+#include "storage/proc.h"
#include "storage/procarray.h"
+#include "storage/sinvaladt.h"
#include "storage/smgr.h"
#include "utils/builtins.h"
+#include "utils/memutils.h"
+#include "utils/timestamp.h"
/*
#define TWOPHASE_DIR "pg_twophase"
/* GUC variable, can't be changed after startup */
-int max_prepared_xacts = 5;
+int max_prepared_xacts = 0;
/*
* This struct describes one global transaction that is in prepared state
* or attempting to become prepared.
*
- * The first component of the struct is a dummy PGPROC that is inserted
- * into the global ProcArray so that the transaction appears to still be
- * running and holding locks. It must be first because we cast pointers
- * to PGPROC and pointers to GlobalTransactionData back and forth.
- *
* The lifecycle of a global transaction is:
*
* 1. After checking that the requested GID is not in use, set up an
* with locking_xid = my own XID and valid = false.
*
* 2. After successfully completing prepare, set valid = true and enter the
- * contained PGPROC into the global ProcArray.
+ * referenced PGPROC into the global ProcArray.
*
* 3. To begin COMMIT PREPARED or ROLLBACK PREPARED, check that the entry
* is valid and its locking_xid is no longer active, then store my current
typedef struct GlobalTransactionData
{
- PGPROC proc; /* dummy proc */
+ GlobalTransaction next; /* list link for free list */
+ int pgprocno; /* ID of associated dummy PGPROC */
+ BackendId dummyBackendId; /* similar to backend id for backends */
TimestampTz prepared_at; /* time of preparation */
XLogRecPtr prepare_lsn; /* XLOG offset of prepare record */
Oid owner; /* ID of user that executed the xact */
TransactionId locking_xid; /* top-level XID of backend working on xact */
bool valid; /* TRUE if fully prepared */
char gid[GIDSIZE]; /* The GID assigned to the prepared xact */
-} GlobalTransactionData;
+} GlobalTransactionData;
/*
* Two Phase Commit shared state. Access to this struct is protected
typedef struct TwoPhaseStateData
{
/* Head of linked list of free GlobalTransactionData structs */
- SHMEM_OFFSET freeGXacts;
+ GlobalTransaction freeGXacts;
/* Number of valid prepXacts entries. */
int numPrepXacts;
int nchildren,
TransactionId *children,
int nrels,
- RelFileNode *rels);
+ RelFileNode *rels,
+ int ninvalmsgs,
+ SharedInvalidationMessage *invalmsgs,
+ bool initfileinval);
static void RecordTransactionAbortPrepared(TransactionId xid,
int nchildren,
TransactionId *children,
int i;
Assert(!found);
- TwoPhaseState->freeGXacts = INVALID_OFFSET;
+ TwoPhaseState->freeGXacts = NULL;
TwoPhaseState->numPrepXacts = 0;
/*
sizeof(GlobalTransaction) * max_prepared_xacts));
for (i = 0; i < max_prepared_xacts; i++)
{
- gxacts[i].proc.links.next = TwoPhaseState->freeGXacts;
- TwoPhaseState->freeGXacts = MAKE_OFFSET(&gxacts[i]);
+ /* insert into linked list */
+ gxacts[i].next = TwoPhaseState->freeGXacts;
+ TwoPhaseState->freeGXacts = &gxacts[i];
+
+ /* associate it with a PGPROC assigned by InitProcGlobal */
+ gxacts[i].pgprocno = PreparedXactProcs[i].pgprocno;
+
+ /*
+ * Assign a unique ID for each dummy proc, so that the range of
+ * dummy backend IDs immediately follows the range of normal
+ * backend IDs. We don't dare to assign a real backend ID to dummy
+ * procs, because prepared transactions don't take part in cache
+ * invalidation like a real backend ID would imply, but having a
+ * unique ID for them is nevertheless handy. This arrangement
+ * allows you to allocate an array of size (MaxBackends +
+ * max_prepared_xacts + 1), and have a slot for every backend and
+ * prepared transaction. Currently multixact.c uses that
+ * technique.
+ */
+ gxacts[i].dummyBackendId = MaxBackends + 1 + i;
}
}
else
TimestampTz prepared_at, Oid owner, Oid databaseid)
{
GlobalTransaction gxact;
+ PGPROC *proc;
+ PGXACT *pgxact;
int i;
if (strlen(gid) >= GIDSIZE)
errmsg("transaction identifier \"%s\" is too long",
gid)));
+ /* fail immediately if feature is disabled */
+ if (max_prepared_xacts == 0)
+ ereport(ERROR,
+ (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+ errmsg("prepared transactions are disabled"),
+ errhint("Set max_prepared_transactions to a nonzero value.")));
+
LWLockAcquire(TwoPhaseStateLock, LW_EXCLUSIVE);
/*
TwoPhaseState->numPrepXacts--;
TwoPhaseState->prepXacts[i] = TwoPhaseState->prepXacts[TwoPhaseState->numPrepXacts];
/* and put it back in the freelist */
- gxact->proc.links.next = TwoPhaseState->freeGXacts;
- TwoPhaseState->freeGXacts = MAKE_OFFSET(gxact);
+ gxact->next = TwoPhaseState->freeGXacts;
+ TwoPhaseState->freeGXacts = gxact;
/* Back up index count too, so we don't miss scanning one */
i--;
}
}
/* Get a free gxact from the freelist */
- if (TwoPhaseState->freeGXacts == INVALID_OFFSET)
+ if (TwoPhaseState->freeGXacts == NULL)
ereport(ERROR,
(errcode(ERRCODE_OUT_OF_MEMORY),
errmsg("maximum number of prepared transactions reached"),
errhint("Increase max_prepared_transactions (currently %d).",
max_prepared_xacts)));
- gxact = (GlobalTransaction) MAKE_PTR(TwoPhaseState->freeGXacts);
- TwoPhaseState->freeGXacts = gxact->proc.links.next;
+ gxact = TwoPhaseState->freeGXacts;
+ TwoPhaseState->freeGXacts = gxact->next;
+
+ proc = &ProcGlobal->allProcs[gxact->pgprocno];
+ pgxact = &ProcGlobal->allPgXact[gxact->pgprocno];
- /* Initialize it */
- MemSet(&gxact->proc, 0, sizeof(PGPROC));
- SHMQueueElemInit(&(gxact->proc.links));
- gxact->proc.waitStatus = STATUS_OK;
+ /* Initialize the PGPROC entry */
+ MemSet(proc, 0, sizeof(PGPROC));
+ proc->pgprocno = gxact->pgprocno;
+ SHMQueueElemInit(&(proc->links));
+ proc->waitStatus = STATUS_OK;
/* We set up the gxact's VXID as InvalidBackendId/XID */
- gxact->proc.lxid = (LocalTransactionId) xid;
- gxact->proc.xid = xid;
- gxact->proc.xmin = InvalidTransactionId;
- gxact->proc.pid = 0;
- gxact->proc.backendId = InvalidBackendId;
- gxact->proc.databaseId = databaseid;
- gxact->proc.roleId = owner;
- gxact->proc.inCommit = false;
- gxact->proc.inVacuum = false;
- gxact->proc.isAutovacuum = false;
- gxact->proc.lwWaiting = false;
- gxact->proc.lwExclusive = false;
- gxact->proc.lwWaitLink = NULL;
- gxact->proc.waitLock = NULL;
- gxact->proc.waitProcLock = NULL;
+ proc->lxid = (LocalTransactionId) xid;
+ pgxact->xid = xid;
+ pgxact->xmin = InvalidTransactionId;
+ pgxact->delayChkpt = false;
+ pgxact->vacuumFlags = 0;
+ proc->pid = 0;
+ proc->backendId = InvalidBackendId;
+ proc->databaseId = databaseid;
+ proc->roleId = owner;
+ proc->lwWaiting = false;
+ proc->lwWaitMode = 0;
+ proc->lwWaitLink = NULL;
+ proc->waitLock = NULL;
+ proc->waitProcLock = NULL;
for (i = 0; i < NUM_LOCK_PARTITIONS; i++)
- SHMQueueInit(&(gxact->proc.myProcLocks[i]));
+ SHMQueueInit(&(proc->myProcLocks[i]));
/* subxid data must be filled later by GXactLoadSubxactData */
- gxact->proc.subxids.overflowed = false;
- gxact->proc.subxids.nxids = 0;
+ pgxact->overflowed = false;
+ pgxact->nxids = 0;
gxact->prepared_at = prepared_at;
/* initialize LSN to 0 (start of WAL) */
- gxact->prepare_lsn.xlogid = 0;
- gxact->prepare_lsn.xrecoff = 0;
+ gxact->prepare_lsn = 0;
gxact->owner = owner;
gxact->locking_xid = xid;
gxact->valid = false;
GXactLoadSubxactData(GlobalTransaction gxact, int nsubxacts,
TransactionId *children)
{
+ PGPROC *proc = &ProcGlobal->allProcs[gxact->pgprocno];
+ PGXACT *pgxact = &ProcGlobal->allPgXact[gxact->pgprocno];
+
/* We need no extra lock since the GXACT isn't valid yet */
if (nsubxacts > PGPROC_MAX_CACHED_SUBXIDS)
{
- gxact->proc.subxids.overflowed = true;
+ pgxact->overflowed = true;
nsubxacts = PGPROC_MAX_CACHED_SUBXIDS;
}
if (nsubxacts > 0)
{
- memcpy(gxact->proc.subxids.xids, children,
+ memcpy(proc->subxids.xids, children,
nsubxacts * sizeof(TransactionId));
- gxact->proc.subxids.nxids = nsubxacts;
+ pgxact->nxids = nsubxacts;
}
}
* Put it into the global ProcArray so TransactionIdIsInProgress considers
* the XID as still running.
*/
- ProcArrayAdd(&gxact->proc);
+ ProcArrayAdd(&ProcGlobal->allProcs[gxact->pgprocno]);
}
/*
for (i = 0; i < TwoPhaseState->numPrepXacts; i++)
{
GlobalTransaction gxact = TwoPhaseState->prepXacts[i];
+ PGPROC *proc = &ProcGlobal->allProcs[gxact->pgprocno];
/* Ignore not-yet-valid GIDs */
if (!gxact->valid)
errhint("Must be superuser or the user that prepared the transaction.")));
/*
- * Note: it probably would be possible to allow committing from another
- * database; but at the moment NOTIFY is known not to work and there
- * may be some other issues as well. Hence disallow until someone
- * gets motivated to make it work.
+ * Note: it probably would be possible to allow committing from
+ * another database; but at the moment NOTIFY is known not to work and
+ * there may be some other issues as well. Hence disallow until
+ * someone gets motivated to make it work.
*/
- if (MyDatabaseId != gxact->proc.databaseId)
+ if (MyDatabaseId != proc->databaseId)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
- errmsg("prepared transaction belongs to another database"),
+ errmsg("prepared transaction belongs to another database"),
errhint("Connect to the database where the transaction was prepared to finish it.")));
/* OK for me to lock it */
TwoPhaseState->prepXacts[i] = TwoPhaseState->prepXacts[TwoPhaseState->numPrepXacts];
/* and put it back in the freelist */
- gxact->proc.links.next = TwoPhaseState->freeGXacts;
- TwoPhaseState->freeGXacts = MAKE_OFFSET(gxact);
+ gxact->next = TwoPhaseState->freeGXacts;
+ TwoPhaseState->freeGXacts = gxact;
LWLockRelease(TwoPhaseStateLock);
for (i = 0; i < TwoPhaseState->numPrepXacts; i++)
{
GlobalTransaction gxact = TwoPhaseState->prepXacts[i];
+ PGXACT *pgxact = &ProcGlobal->allPgXact[gxact->pgprocno];
- if (gxact->valid && gxact->proc.xid == xid)
+ if (gxact->valid && pgxact->xid == xid)
{
result = true;
break;
while (status->array != NULL && status->currIdx < status->ngxacts)
{
GlobalTransaction gxact = &status->array[status->currIdx++];
+ PGPROC *proc = &ProcGlobal->allProcs[gxact->pgprocno];
+ PGXACT *pgxact = &ProcGlobal->allPgXact[gxact->pgprocno];
Datum values[5];
bool nulls[5];
HeapTuple tuple;
MemSet(values, 0, sizeof(values));
MemSet(nulls, 0, sizeof(nulls));
- values[0] = TransactionIdGetDatum(gxact->proc.xid);
- values[1] = DirectFunctionCall1(textin, CStringGetDatum(gxact->gid));
+ values[0] = TransactionIdGetDatum(pgxact->xid);
+ values[1] = CStringGetTextDatum(gxact->gid);
values[2] = TimestampTzGetDatum(gxact->prepared_at);
values[3] = ObjectIdGetDatum(gxact->owner);
- values[4] = ObjectIdGetDatum(gxact->proc.databaseId);
+ values[4] = ObjectIdGetDatum(proc->databaseId);
tuple = heap_form_tuple(funcctx->tuple_desc, values, nulls);
result = HeapTupleGetDatum(tuple);
}
/*
- * TwoPhaseGetDummyProc
- * Get the PGPROC that represents a prepared transaction specified by XID
+ * TwoPhaseGetGXact
+ * Get the GlobalTransaction struct for a prepared transaction
+ * specified by XID
*/
-PGPROC *
-TwoPhaseGetDummyProc(TransactionId xid)
+static GlobalTransaction
+TwoPhaseGetGXact(TransactionId xid)
{
- PGPROC *result = NULL;
+ GlobalTransaction result = NULL;
int i;
static TransactionId cached_xid = InvalidTransactionId;
- static PGPROC *cached_proc = NULL;
+ static GlobalTransaction cached_gxact = NULL;
/*
* During a recovery, COMMIT PREPARED, or ABORT PREPARED, we'll be called
* repeatedly for the same XID. We can save work with a simple cache.
*/
if (xid == cached_xid)
- return cached_proc;
+ return cached_gxact;
LWLockAcquire(TwoPhaseStateLock, LW_SHARED);
for (i = 0; i < TwoPhaseState->numPrepXacts; i++)
{
GlobalTransaction gxact = TwoPhaseState->prepXacts[i];
+ PGXACT *pgxact = &ProcGlobal->allPgXact[gxact->pgprocno];
- if (gxact->proc.xid == xid)
+ if (pgxact->xid == xid)
{
- result = &gxact->proc;
+ result = gxact;
break;
}
}
LWLockRelease(TwoPhaseStateLock);
if (result == NULL) /* should not happen */
- elog(ERROR, "failed to find dummy PGPROC for xid %u", xid);
+ elog(ERROR, "failed to find GlobalTransaction for xid %u", xid);
cached_xid = xid;
- cached_proc = result;
+ cached_gxact = result;
return result;
}
+/*
+ * TwoPhaseGetDummyProc
+ * Get the dummy backend ID for prepared transaction specified by XID
+ *
+ * Dummy backend IDs are similar to real backend IDs of real backends.
+ * They start at MaxBackends + 1, and are unique across all currently active
+ * real backends and prepared transactions.
+ */
+BackendId
+TwoPhaseGetDummyBackendId(TransactionId xid)
+{
+ GlobalTransaction gxact = TwoPhaseGetGXact(xid);
+
+ return gxact->dummyBackendId;
+}
+
+/*
+ * TwoPhaseGetDummyProc
+ * Get the PGPROC that represents a prepared transaction specified by XID
+ */
+PGPROC *
+TwoPhaseGetDummyProc(TransactionId xid)
+{
+ GlobalTransaction gxact = TwoPhaseGetGXact(xid);
+
+ return &ProcGlobal->allProcs[gxact->pgprocno];
+}
+
/************************************************************************/
/* State file support */
/************************************************************************/
* 2. TransactionId[] (subtransactions)
* 3. RelFileNode[] (files to be deleted at commit)
* 4. RelFileNode[] (files to be deleted at abort)
- * 5. TwoPhaseRecordOnDisk
- * 6. ...
- * 7. TwoPhaseRecordOnDisk (end sentinel, rmid == TWOPHASE_RM_END_ID)
- * 8. CRC32
+ * 5. SharedInvalidationMessage[] (inval messages to be sent at commit)
+ * 6. TwoPhaseRecordOnDisk
+ * 7. ...
+ * 8. TwoPhaseRecordOnDisk (end sentinel, rmid == TWOPHASE_RM_END_ID)
+ * 9. CRC32
*
* Each segment except the final CRC32 is MAXALIGN'd.
*/
/*
* Header for a 2PC state file
*/
-#define TWOPHASE_MAGIC 0x57F94531 /* format identifier */
+#define TWOPHASE_MAGIC 0x57F94532 /* format identifier */
typedef struct TwoPhaseFileHeader
{
int32 nsubxacts; /* number of following subxact XIDs */
int32 ncommitrels; /* number of delete-on-commit rels */
int32 nabortrels; /* number of delete-on-abort rels */
+ int32 ninvalmsgs; /* number of cache invalidation messages */
+ bool initfileinval; /* does relcache init file need invalidation? */
char gid[GIDSIZE]; /* GID for transaction */
} TwoPhaseFileHeader;
void
StartPrepare(GlobalTransaction gxact)
{
- TransactionId xid = gxact->proc.xid;
+ PGPROC *proc = &ProcGlobal->allProcs[gxact->pgprocno];
+ PGXACT *pgxact = &ProcGlobal->allPgXact[gxact->pgprocno];
+ TransactionId xid = pgxact->xid;
TwoPhaseFileHeader hdr;
TransactionId *children;
RelFileNode *commitrels;
RelFileNode *abortrels;
+ SharedInvalidationMessage *invalmsgs;
/* Initialize linked list */
records.head = palloc0(sizeof(XLogRecData));
hdr.magic = TWOPHASE_MAGIC;
hdr.total_len = 0; /* EndPrepare will fill this in */
hdr.xid = xid;
- hdr.database = gxact->proc.databaseId;
+ hdr.database = proc->databaseId;
hdr.prepared_at = gxact->prepared_at;
hdr.owner = gxact->owner;
hdr.nsubxacts = xactGetCommittedChildren(&children);
- hdr.ncommitrels = smgrGetPendingDeletes(true, &commitrels, NULL);
- hdr.nabortrels = smgrGetPendingDeletes(false, &abortrels, NULL);
+ hdr.ncommitrels = smgrGetPendingDeletes(true, &commitrels);
+ hdr.nabortrels = smgrGetPendingDeletes(false, &abortrels);
+ hdr.ninvalmsgs = xactGetCommittedInvalidationMessages(&invalmsgs,
+ &hdr.initfileinval);
StrNCpy(hdr.gid, gxact->gid, GIDSIZE);
save_state_data(&hdr, sizeof(TwoPhaseFileHeader));
- /* Add the additional info about subxacts and deletable files */
+ /*
+ * Add the additional info about subxacts, deletable files and cache
+ * invalidation messages.
+ */
if (hdr.nsubxacts > 0)
{
save_state_data(children, hdr.nsubxacts * sizeof(TransactionId));
/* While we have the child-xact data, stuff it in the gxact too */
GXactLoadSubxactData(gxact, hdr.nsubxacts, children);
- pfree(children);
}
if (hdr.ncommitrels > 0)
{
save_state_data(abortrels, hdr.nabortrels * sizeof(RelFileNode));
pfree(abortrels);
}
+ if (hdr.ninvalmsgs > 0)
+ {
+ save_state_data(invalmsgs,
+ hdr.ninvalmsgs * sizeof(SharedInvalidationMessage));
+ pfree(invalmsgs);
+ }
}
/*
void
EndPrepare(GlobalTransaction gxact)
{
- TransactionId xid = gxact->proc.xid;
+ PGXACT *pgxact = &ProcGlobal->allPgXact[gxact->pgprocno];
+ TransactionId xid = pgxact->xid;
TwoPhaseFileHeader *hdr;
char path[MAXPGPATH];
XLogRecData *record;
Assert(hdr->magic == TWOPHASE_MAGIC);
hdr->total_len = records.total_len + sizeof(pg_crc32);
+ /*
+ * If the file size exceeds MaxAllocSize, we won't be able to read it in
+ * ReadTwoPhaseFile. Check for that now, rather than fail at commit time.
+ */
+ if (hdr->total_len > MaxAllocSize)
+ ereport(ERROR,
+ (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+ errmsg("two-phase state file maximum length exceeded")));
+
/*
* Create the 2PC state file.
- *
- * Note: because we use BasicOpenFile(), we are responsible for ensuring
- * the FD gets closed in any error exit path. Once we get into the
- * critical section, though, it doesn't matter since any failure causes
- * PANIC anyway.
*/
TwoPhaseFilePath(path, xid);
- fd = BasicOpenFile(path,
- O_CREAT | O_EXCL | O_WRONLY | PG_BINARY,
- S_IRUSR | S_IWUSR);
+ fd = OpenTransientFile(path,
+ O_CREAT | O_EXCL | O_WRONLY | PG_BINARY,
+ S_IRUSR | S_IWUSR);
if (fd < 0)
ereport(ERROR,
(errcode_for_file_access(),
COMP_CRC32(statefile_crc, record->data, record->len);
if ((write(fd, record->data, record->len)) != record->len)
{
- close(fd);
+ CloseTransientFile(fd);
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not write two-phase state file: %m")));
if ((write(fd, &bogus_crc, sizeof(pg_crc32))) != sizeof(pg_crc32))
{
- close(fd);
+ CloseTransientFile(fd);
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not write two-phase state file: %m")));
/* Back up to prepare for rewriting the CRC */
if (lseek(fd, -((off_t) sizeof(pg_crc32)), SEEK_CUR) < 0)
{
- close(fd);
+ CloseTransientFile(fd);
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not seek in two-phase state file: %m")));
* out the correct state file CRC, we have an inconsistency: the xact is
* prepared according to WAL but not according to our on-disk state. We
* use a critical section to force a PANIC if we are unable to complete
- * the write --- then, WAL replay should repair the inconsistency. The
+ * the write --- then, WAL replay should repair the inconsistency. The
* odds of a PANIC actually occurring should be very tiny given that we
* were able to write the bogus CRC above.
*
- * We have to set inCommit here, too; otherwise a checkpoint
- * starting immediately after the WAL record is inserted could complete
- * without fsync'ing our state file. (This is essentially the same kind
- * of race condition as the COMMIT-to-clog-write case that
- * RecordTransactionCommit uses inCommit for; see notes there.)
+ * We have to set delayChkpt here, too; otherwise a checkpoint starting
+ * immediately after the WAL record is inserted could complete without
+ * fsync'ing our state file. (This is essentially the same kind of race
+ * condition as the COMMIT-to-clog-write case that RecordTransactionCommit
+ * uses delayChkpt for; see notes there.)
*
* We save the PREPARE record's location in the gxact for later use by
* CheckPointTwoPhase.
*/
START_CRIT_SECTION();
- MyProc->inCommit = true;
+ MyPgXact->delayChkpt = true;
gxact->prepare_lsn = XLogInsert(RM_XACT_ID, XLOG_XACT_PREPARE,
records.head);
/* write correct CRC and close file */
if ((write(fd, &statefile_crc, sizeof(pg_crc32))) != sizeof(pg_crc32))
{
- close(fd);
+ CloseTransientFile(fd);
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not write two-phase state file: %m")));
}
- if (close(fd) != 0)
+ if (CloseTransientFile(fd) != 0)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not close two-phase state file: %m")));
/*
- * Mark the prepared transaction as valid. As soon as xact.c marks MyProc
- * as not running our XID (which it will do immediately after this
- * function returns), others can commit/rollback the xact.
+ * Mark the prepared transaction as valid. As soon as xact.c marks
+ * MyPgXact as not running our XID (which it will do immediately after
+ * this function returns), others can commit/rollback the xact.
*
* NB: a side effect of this is to make a dummy ProcArray entry for the
- * prepared XID. This must happen before we clear the XID from MyProc,
+ * prepared XID. This must happen before we clear the XID from MyPgXact,
* else there is a window where the XID is not running according to
* TransactionIdIsInProgress, and onlookers would be entitled to assume
* the xact crashed. Instead we have a window where the same XID appears
MarkAsPrepared(gxact);
/*
- * Now we can mark ourselves as out of the commit critical section:
- * a checkpoint starting after this will certainly see the gxact as a
+ * Now we can mark ourselves as out of the commit critical section: a
+ * checkpoint starting after this will certainly see the gxact as a
* candidate for fsyncing.
*/
- MyProc->inCommit = false;
+ MyPgXact->delayChkpt = false;
END_CRIT_SECTION();
+ /*
+ * Wait for synchronous replication, if required.
+ *
+ * Note that at this stage we have marked the prepare, but still show as
+ * running in the procarray (twice!) and continue to hold locks.
+ */
+ SyncRepWaitForLSN(gxact->prepare_lsn);
+
records.tail = records.head = NULL;
}
* contents of the file. Otherwise return NULL.
*/
static char *
-ReadTwoPhaseFile(TransactionId xid)
+ReadTwoPhaseFile(TransactionId xid, bool give_warnings)
{
char path[MAXPGPATH];
char *buf;
TwoPhaseFilePath(path, xid);
- fd = BasicOpenFile(path, O_RDONLY | PG_BINARY, 0);
+ fd = OpenTransientFile(path, O_RDONLY | PG_BINARY, 0);
if (fd < 0)
{
- ereport(WARNING,
- (errcode_for_file_access(),
- errmsg("could not open two-phase state file \"%s\": %m",
- path)));
+ if (give_warnings)
+ ereport(WARNING,
+ (errcode_for_file_access(),
+ errmsg("could not open two-phase state file \"%s\": %m",
+ path)));
return NULL;
}
/*
* Check file length. We can determine a lower bound pretty easily. We
- * set an upper bound mainly to avoid palloc() failure on a corrupt file.
+ * set an upper bound to avoid palloc() failure on a corrupt file, though
+ * we can't guarantee that we won't get an out of memory error anyway,
+ * even on a valid file.
*/
if (fstat(fd, &stat))
{
- close(fd);
- ereport(WARNING,
- (errcode_for_file_access(),
- errmsg("could not stat two-phase state file \"%s\": %m",
- path)));
+ CloseTransientFile(fd);
+ if (give_warnings)
+ ereport(WARNING,
+ (errcode_for_file_access(),
+ errmsg("could not stat two-phase state file \"%s\": %m",
+ path)));
return NULL;
}
if (stat.st_size < (MAXALIGN(sizeof(TwoPhaseFileHeader)) +
MAXALIGN(sizeof(TwoPhaseRecordOnDisk)) +
sizeof(pg_crc32)) ||
- stat.st_size > 10000000)
+ stat.st_size > MaxAllocSize)
{
- close(fd);
+ CloseTransientFile(fd);
return NULL;
}
crc_offset = stat.st_size - sizeof(pg_crc32);
if (crc_offset != MAXALIGN(crc_offset))
{
- close(fd);
+ CloseTransientFile(fd);
return NULL;
}
if (read(fd, buf, stat.st_size) != stat.st_size)
{
- close(fd);
- ereport(WARNING,
- (errcode_for_file_access(),
- errmsg("could not read two-phase state file \"%s\": %m",
- path)));
+ CloseTransientFile(fd);
+ if (give_warnings)
+ ereport(WARNING,
+ (errcode_for_file_access(),
+ errmsg("could not read two-phase state file \"%s\": %m",
+ path)));
pfree(buf);
return NULL;
}
- close(fd);
+ CloseTransientFile(fd);
hdr = (TwoPhaseFileHeader *) buf;
if (hdr->magic != TWOPHASE_MAGIC || hdr->total_len != stat.st_size)
return buf;
}
+/*
+ * Confirms an xid is prepared, during recovery
+ */
+bool
+StandbyTransactionIdIsPrepared(TransactionId xid)
+{
+ char *buf;
+ TwoPhaseFileHeader *hdr;
+ bool result;
+
+ Assert(TransactionIdIsValid(xid));
+
+ if (max_prepared_xacts <= 0)
+ return false; /* nothing to do */
+
+ /* Read and validate file */
+ buf = ReadTwoPhaseFile(xid, false);
+ if (buf == NULL)
+ return false;
+
+ /* Check header also */
+ hdr = (TwoPhaseFileHeader *) buf;
+ result = TransactionIdEquals(hdr->xid, xid);
+ pfree(buf);
+
+ return result;
+}
/*
* FinishPreparedTransaction: execute COMMIT PREPARED or ROLLBACK PREPARED
FinishPreparedTransaction(const char *gid, bool isCommit)
{
GlobalTransaction gxact;
+ PGPROC *proc;
+ PGXACT *pgxact;
TransactionId xid;
char *buf;
char *bufptr;
TransactionId *children;
RelFileNode *commitrels;
RelFileNode *abortrels;
+ RelFileNode *delrels;
+ int ndelrels;
+ SharedInvalidationMessage *invalmsgs;
int i;
/*
* try to commit the same GID at once.
*/
gxact = LockGXact(gid, GetUserId());
- xid = gxact->proc.xid;
+ proc = &ProcGlobal->allProcs[gxact->pgprocno];
+ pgxact = &ProcGlobal->allPgXact[gxact->pgprocno];
+ xid = pgxact->xid;
/*
* Read and validate the state file
*/
- buf = ReadTwoPhaseFile(xid);
+ buf = ReadTwoPhaseFile(xid, true);
if (buf == NULL)
ereport(ERROR,
(errcode(ERRCODE_DATA_CORRUPTED),
bufptr += MAXALIGN(hdr->ncommitrels * sizeof(RelFileNode));
abortrels = (RelFileNode *) bufptr;
bufptr += MAXALIGN(hdr->nabortrels * sizeof(RelFileNode));
+ invalmsgs = (SharedInvalidationMessage *) bufptr;
+ bufptr += MAXALIGN(hdr->ninvalmsgs * sizeof(SharedInvalidationMessage));
/* compute latestXid among all children */
latestXid = TransactionIdLatest(xid, hdr->nsubxacts, children);
if (isCommit)
RecordTransactionCommitPrepared(xid,
hdr->nsubxacts, children,
- hdr->ncommitrels, commitrels);
+ hdr->ncommitrels, commitrels,
+ hdr->ninvalmsgs, invalmsgs,
+ hdr->initfileinval);
else
RecordTransactionAbortPrepared(xid,
hdr->nsubxacts, children,
hdr->nabortrels, abortrels);
- ProcArrayRemove(&gxact->proc, latestXid);
+ ProcArrayRemove(proc, latestXid);
/*
* In case we fail while running the callbacks, mark the gxact invalid so
* no one else will try to commit/rollback, and so it can be recycled
- * properly later. It is still locked by our XID so it won't go away yet.
+ * properly later. It is still locked by our XID so it won't go away yet.
*
* (We assume it's safe to do this without taking TwoPhaseStateLock.)
*/
*/
if (isCommit)
{
- for (i = 0; i < hdr->ncommitrels; i++)
- smgrdounlink(smgropen(commitrels[i]), false, false);
+ delrels = commitrels;
+ ndelrels = hdr->ncommitrels;
}
else
{
- for (i = 0; i < hdr->nabortrels; i++)
- smgrdounlink(smgropen(abortrels[i]), false, false);
+ delrels = abortrels;
+ ndelrels = hdr->nabortrels;
+ }
+ for (i = 0; i < ndelrels; i++)
+ {
+ SMgrRelation srel = smgropen(delrels[i], InvalidBackendId);
+
+ smgrdounlink(srel, false);
+ smgrclose(srel);
}
+ /*
+ * Handle cache invalidation messages.
+ *
+ * Relcache init file invalidation requires processing both before and
+ * after we send the SI messages. See AtEOXact_Inval()
+ */
+ if (hdr->initfileinval)
+ RelationCacheInitFilePreInvalidate();
+ SendSharedInvalidMessages(invalmsgs, hdr->ninvalmsgs);
+ if (hdr->initfileinval)
+ RelationCacheInitFilePostInvalidate();
+
/* And now do the callbacks */
if (isCommit)
ProcessRecords(bufptr, xid, twophase_postcommit_callbacks);
else
ProcessRecords(bufptr, xid, twophase_postabort_callbacks);
+ PredicateLockTwoPhaseFinish(xid, isCommit);
+
/* Count the prepared xact as committed or aborted */
AtEOXact_PgStat(isCommit);
if (errno != ENOENT || giveWarning)
ereport(WARNING,
(errcode_for_file_access(),
- errmsg("could not remove two-phase state file \"%s\": %m",
- path)));
+ errmsg("could not remove two-phase state file \"%s\": %m",
+ path)));
}
/*
TwoPhaseFilePath(path, xid);
- fd = BasicOpenFile(path,
- O_CREAT | O_TRUNC | O_WRONLY | PG_BINARY,
- S_IRUSR | S_IWUSR);
+ fd = OpenTransientFile(path,
+ O_CREAT | O_TRUNC | O_WRONLY | PG_BINARY,
+ S_IRUSR | S_IWUSR);
if (fd < 0)
ereport(ERROR,
(errcode_for_file_access(),
/* Write content and CRC */
if (write(fd, content, len) != len)
{
- close(fd);
+ CloseTransientFile(fd);
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not write two-phase state file: %m")));
}
if (write(fd, &statefile_crc, sizeof(pg_crc32)) != sizeof(pg_crc32))
{
- close(fd);
+ CloseTransientFile(fd);
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not write two-phase state file: %m")));
*/
if (pg_fsync(fd) != 0)
{
- close(fd);
+ CloseTransientFile(fd);
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not fsync two-phase state file: %m")));
}
- if (close(fd) != 0)
+ if (CloseTransientFile(fd) != 0)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not close two-phase state file: %m")));
*
* This approach creates a race condition: someone else could delete a
* GXACT between the time we release TwoPhaseStateLock and the time we try
- * to open its state file. We handle this by special-casing ENOENT
+ * to open its state file. We handle this by special-casing ENOENT
* failures: if we see that, we verify that the GXACT is no longer valid,
* and if so ignore the failure.
*/
if (max_prepared_xacts <= 0)
return; /* nothing to do */
+
+ TRACE_POSTGRESQL_TWOPHASE_CHECKPOINT_START();
+
xids = (TransactionId *) palloc(max_prepared_xacts * sizeof(TransactionId));
nxids = 0;
for (i = 0; i < TwoPhaseState->numPrepXacts; i++)
{
GlobalTransaction gxact = TwoPhaseState->prepXacts[i];
+ PGXACT *pgxact = &ProcGlobal->allPgXact[gxact->pgprocno];
if (gxact->valid &&
- XLByteLE(gxact->prepare_lsn, redo_horizon))
- xids[nxids++] = gxact->proc.xid;
+ gxact->prepare_lsn <= redo_horizon)
+ xids[nxids++] = pgxact->xid;
}
LWLockRelease(TwoPhaseStateLock);
TwoPhaseFilePath(path, xid);
- fd = BasicOpenFile(path, O_RDWR | PG_BINARY, 0);
+ fd = OpenTransientFile(path, O_RDWR | PG_BINARY, 0);
if (fd < 0)
{
if (errno == ENOENT)
if (pg_fsync(fd) != 0)
{
- close(fd);
+ CloseTransientFile(fd);
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not fsync two-phase state file \"%s\": %m",
path)));
}
- if (close(fd) != 0)
+ if (CloseTransientFile(fd) != 0)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not close two-phase state file \"%s\": %m",
}
pfree(xids);
+
+ TRACE_POSTGRESQL_TWOPHASE_CHECKPOINT_DONE();
}
/*
*
* We throw away any prepared xacts with main XID beyond nextXid --- if any
* are present, it suggests that the DBA has done a PITR recovery to an
- * earlier point in time without cleaning out pg_twophase. We dare not
+ * earlier point in time without cleaning out pg_twophase. We dare not
* try to recover such prepared xacts since they likely depend on database
* state that doesn't exist now.
*
* Our other responsibility is to determine and return the oldest valid XID
* among the prepared xacts (if none, return ShmemVariableCache->nextXid).
* This is needed to synchronize pg_subtrans startup properly.
+ *
+ * If xids_p and nxids_p are not NULL, pointer to a palloc'd array of all
+ * top-level xids is stored in *xids_p. The number of entries in the array
+ * is returned in *nxids_p.
*/
TransactionId
-PrescanPreparedTransactions(void)
+PrescanPreparedTransactions(TransactionId **xids_p, int *nxids_p)
{
TransactionId origNextXid = ShmemVariableCache->nextXid;
TransactionId result = origNextXid;
DIR *cldir;
struct dirent *clde;
+ TransactionId *xids = NULL;
+ int nxids = 0;
+ int allocsize = 0;
cldir = AllocateDir(TWOPHASE_DIR);
while ((clde = ReadDir(cldir, TWOPHASE_DIR)) != NULL)
*/
/* Read and validate file */
- buf = ReadTwoPhaseFile(xid);
+ buf = ReadTwoPhaseFile(xid, true);
if (buf == NULL)
{
ereport(WARNING,
- (errmsg("removing corrupt two-phase state file \"%s\"",
- clde->d_name)));
+ (errmsg("removing corrupt two-phase state file \"%s\"",
+ clde->d_name)));
RemoveTwoPhaseFile(xid, true);
continue;
}
if (!TransactionIdEquals(hdr->xid, xid))
{
ereport(WARNING,
- (errmsg("removing corrupt two-phase state file \"%s\"",
- clde->d_name)));
+ (errmsg("removing corrupt two-phase state file \"%s\"",
+ clde->d_name)));
RemoveTwoPhaseFile(xid, true);
pfree(buf);
continue;
/*
* Examine subtransaction XIDs ... they should all follow main
* XID, and they may force us to advance nextXid.
+ *
+ * We don't expect anyone else to modify nextXid, hence we don't
+ * need to hold a lock while examining it. We still acquire the
+ * lock to modify it, though.
*/
subxids = (TransactionId *)
(buf + MAXALIGN(sizeof(TwoPhaseFileHeader)));
if (TransactionIdFollowsOrEquals(subxid,
ShmemVariableCache->nextXid))
{
+ LWLockAcquire(XidGenLock, LW_EXCLUSIVE);
ShmemVariableCache->nextXid = subxid;
TransactionIdAdvance(ShmemVariableCache->nextXid);
+ LWLockRelease(XidGenLock);
+ }
+ }
+
+
+ if (xids_p)
+ {
+ if (nxids == allocsize)
+ {
+ if (nxids == 0)
+ {
+ allocsize = 10;
+ xids = palloc(allocsize * sizeof(TransactionId));
+ }
+ else
+ {
+ allocsize = allocsize * 2;
+ xids = repalloc(xids, allocsize * sizeof(TransactionId));
+ }
}
+ xids[nxids++] = xid;
}
pfree(buf);
}
FreeDir(cldir);
+ if (xids_p)
+ {
+ *xids_p = xids;
+ *nxids_p = nxids;
+ }
+
return result;
}
+/*
+ * StandbyRecoverPreparedTransactions
+ *
+ * Scan the pg_twophase directory and setup all the required information to
+ * allow standby queries to treat prepared transactions as still active.
+ * This is never called at the end of recovery - we use
+ * RecoverPreparedTransactions() at that point.
+ *
+ * Currently we simply call SubTransSetParent() for any subxids of prepared
+ * transactions. If overwriteOK is true, it's OK if some XIDs have already
+ * been marked in pg_subtrans.
+ */
+void
+StandbyRecoverPreparedTransactions(bool overwriteOK)
+{
+ DIR *cldir;
+ struct dirent *clde;
+
+ cldir = AllocateDir(TWOPHASE_DIR);
+ while ((clde = ReadDir(cldir, TWOPHASE_DIR)) != NULL)
+ {
+ if (strlen(clde->d_name) == 8 &&
+ strspn(clde->d_name, "0123456789ABCDEF") == 8)
+ {
+ TransactionId xid;
+ char *buf;
+ TwoPhaseFileHeader *hdr;
+ TransactionId *subxids;
+ int i;
+
+ xid = (TransactionId) strtoul(clde->d_name, NULL, 16);
+
+ /* Already processed? */
+ if (TransactionIdDidCommit(xid) || TransactionIdDidAbort(xid))
+ {
+ ereport(WARNING,
+ (errmsg("removing stale two-phase state file \"%s\"",
+ clde->d_name)));
+ RemoveTwoPhaseFile(xid, true);
+ continue;
+ }
+
+ /* Read and validate file */
+ buf = ReadTwoPhaseFile(xid, true);
+ if (buf == NULL)
+ {
+ ereport(WARNING,
+ (errmsg("removing corrupt two-phase state file \"%s\"",
+ clde->d_name)));
+ RemoveTwoPhaseFile(xid, true);
+ continue;
+ }
+
+ /* Deconstruct header */
+ hdr = (TwoPhaseFileHeader *) buf;
+ if (!TransactionIdEquals(hdr->xid, xid))
+ {
+ ereport(WARNING,
+ (errmsg("removing corrupt two-phase state file \"%s\"",
+ clde->d_name)));
+ RemoveTwoPhaseFile(xid, true);
+ pfree(buf);
+ continue;
+ }
+
+ /*
+ * Examine subtransaction XIDs ... they should all follow main
+ * XID.
+ */
+ subxids = (TransactionId *)
+ (buf + MAXALIGN(sizeof(TwoPhaseFileHeader)));
+ for (i = 0; i < hdr->nsubxacts; i++)
+ {
+ TransactionId subxid = subxids[i];
+
+ Assert(TransactionIdFollows(subxid, xid));
+ SubTransSetParent(xid, subxid, overwriteOK);
+ }
+ }
+ }
+ FreeDir(cldir);
+}
+
/*
* RecoverPreparedTransactions
*
char dir[MAXPGPATH];
DIR *cldir;
struct dirent *clde;
+ bool overwriteOK = false;
snprintf(dir, MAXPGPATH, "%s", TWOPHASE_DIR);
}
/* Read and validate file */
- buf = ReadTwoPhaseFile(xid);
+ buf = ReadTwoPhaseFile(xid, true);
if (buf == NULL)
{
ereport(WARNING,
- (errmsg("removing corrupt two-phase state file \"%s\"",
- clde->d_name)));
+ (errmsg("removing corrupt two-phase state file \"%s\"",
+ clde->d_name)));
RemoveTwoPhaseFile(xid, true);
continue;
}
bufptr += MAXALIGN(hdr->nsubxacts * sizeof(TransactionId));
bufptr += MAXALIGN(hdr->ncommitrels * sizeof(RelFileNode));
bufptr += MAXALIGN(hdr->nabortrels * sizeof(RelFileNode));
+ bufptr += MAXALIGN(hdr->ninvalmsgs * sizeof(SharedInvalidationMessage));
+
+ /*
+ * It's possible that SubTransSetParent has been set before, if
+ * the prepared transaction generated xid assignment records. Test
+ * here must match one used in AssignTransactionId().
+ */
+ if (InHotStandby && (hdr->nsubxacts >= PGPROC_MAX_CACHED_SUBXIDS ||
+ XLogLogicalInfoActive()))
+ overwriteOK = true;
/*
* Reconstruct subtrans state for the transaction --- needed
* hierarchy, but there's no need to restore that exactly.
*/
for (i = 0; i < hdr->nsubxacts; i++)
- SubTransSetParent(subxids[i], xid);
+ SubTransSetParent(subxids[i], xid, overwriteOK);
/*
* Recreate its GXACT and dummy PGPROC
*/
ProcessRecords(bufptr, xid, twophase_recover_callbacks);
+ /*
+ * Release locks held by the standby process after we process each
+ * prepared transaction. As a result, we don't need too many
+ * additional locks at any one time.
+ */
+ if (InHotStandby)
+ StandbyReleaseLockTree(xid, hdr->nsubxacts, subxids);
+
pfree(buf);
}
}
* RecordTransactionCommitPrepared
*
* This is basically the same as RecordTransactionCommit: in particular,
- * we must set the inCommit flag to avoid a race condition.
+ * we must set the delayChkpt flag to avoid a race condition.
*
* We know the transaction made at least one XLOG entry (its PREPARE),
* so it is never possible to optimize out the commit record.
int nchildren,
TransactionId *children,
int nrels,
- RelFileNode *rels)
+ RelFileNode *rels,
+ int ninvalmsgs,
+ SharedInvalidationMessage *invalmsgs,
+ bool initfileinval)
{
- XLogRecData rdata[3];
+ XLogRecData rdata[4];
int lastrdata = 0;
xl_xact_commit_prepared xlrec;
XLogRecPtr recptr;
START_CRIT_SECTION();
/* See notes in RecordTransactionCommit */
- MyProc->inCommit = true;
+ MyPgXact->delayChkpt = true;
/* Emit the XLOG commit record */
xlrec.xid = xid;
xlrec.crec.xact_time = GetCurrentTimestamp();
+ xlrec.crec.xinfo = initfileinval ? XACT_COMPLETION_UPDATE_RELCACHE_FILE : 0;
+ xlrec.crec.nmsgs = 0;
xlrec.crec.nrels = nrels;
xlrec.crec.nsubxacts = nchildren;
+ xlrec.crec.nmsgs = ninvalmsgs;
+
rdata[0].data = (char *) (&xlrec);
rdata[0].len = MinSizeOfXactCommitPrepared;
rdata[0].buffer = InvalidBuffer;
rdata[2].buffer = InvalidBuffer;
lastrdata = 2;
}
+ /* dump cache invalidation messages */
+ if (ninvalmsgs > 0)
+ {
+ rdata[lastrdata].next = &(rdata[3]);
+ rdata[3].data = (char *) invalmsgs;
+ rdata[3].len = ninvalmsgs * sizeof(SharedInvalidationMessage);
+ rdata[3].buffer = InvalidBuffer;
+ lastrdata = 3;
+ }
rdata[lastrdata].next = NULL;
recptr = XLogInsert(RM_XACT_ID, XLOG_XACT_COMMIT_PREPARED, rdata);
/*
- * We don't currently try to sleep before flush here ... nor is there
- * any support for async commit of a prepared xact (the very idea is
- * probably a contradiction)
+ * We don't currently try to sleep before flush here ... nor is there any
+ * support for async commit of a prepared xact (the very idea is probably
+ * a contradiction)
*/
/* Flush XLOG to disk */
XLogFlush(recptr);
/* Mark the transaction committed in pg_clog */
- TransactionIdCommit(xid);
- /* to avoid race conditions, the parent must commit first */
- TransactionIdCommitTree(nchildren, children);
+ TransactionIdCommitTree(xid, nchildren, children);
/* Checkpoint can proceed now */
- MyProc->inCommit = false;
+ MyPgXact->delayChkpt = false;
END_CRIT_SECTION();
+
+ /*
+ * Wait for synchronous replication, if required.
+ *
+ * Note that at this stage we have marked clog, but still show as running
+ * in the procarray and continue to hold locks.
+ */
+ SyncRepWaitForLSN(recptr);
}
/*
* Mark the transaction aborted in clog. This is not absolutely necessary
* but we may as well do it while we are here.
*/
- TransactionIdAbort(xid);
- TransactionIdAbortTree(nchildren, children);
+ TransactionIdAbortTree(xid, nchildren, children);
END_CRIT_SECTION();
+
+ /*
+ * Wait for synchronous replication, if required.
+ *
+ * Note that at this stage we have marked clog, but still show as running
+ * in the procarray and continue to hold locks.
+ */
+ SyncRepWaitForLSN(recptr);
}
projects / postgresql / blobdiff