* twophase.c
* Two-phase commit support functions.
*
- * Portions Copyright (c) 1996-2010, 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 1.64 2010/09/11 15:48:04 heikki 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/htup.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 "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"
/*
* 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 */
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
sizeof(GlobalTransaction) * max_prepared_xacts));
for (i = 0; i < max_prepared_xacts; i++)
{
- gxacts[i].proc.links.next = (SHM_QUEUE *) TwoPhaseState->freeGXacts;
+ /* 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
TimestampTz prepared_at, Oid owner, Oid databaseid)
{
GlobalTransaction gxact;
+ PGPROC *proc;
+ PGXACT *pgxact;
int i;
if (strlen(gid) >= GIDSIZE)
TwoPhaseState->numPrepXacts--;
TwoPhaseState->prepXacts[i] = TwoPhaseState->prepXacts[TwoPhaseState->numPrepXacts];
/* and put it back in the freelist */
- gxact->proc.links.next = (SHM_QUEUE *) TwoPhaseState->freeGXacts;
+ gxact->next = TwoPhaseState->freeGXacts;
TwoPhaseState->freeGXacts = gxact;
/* Back up index count too, so we don't miss scanning one */
i--;
errhint("Increase max_prepared_transactions (currently %d).",
max_prepared_xacts)));
gxact = TwoPhaseState->freeGXacts;
- TwoPhaseState->freeGXacts = (GlobalTransaction) gxact->proc.links.next;
+ 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.vacuumFlags = 0;
- 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)
/*
* 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
+ * 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"),
TwoPhaseState->prepXacts[i] = TwoPhaseState->prepXacts[TwoPhaseState->numPrepXacts];
/* and put it back in the freelist */
- gxact->proc.links.next = (SHM_QUEUE *) TwoPhaseState->freeGXacts;
+ 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[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 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.
+ * TwoPhaseGetGXact
+ * Get the GlobalTransaction struct for a prepared transaction
+ * specified by XID
*/
-BackendId
-TwoPhaseGetDummyBackendId(TransactionId xid)
-{
- PGPROC *proc = TwoPhaseGetDummyProc(xid);
-
- return ((GlobalTransaction) proc)->dummyBackendId;
-}
-
-/*
- * TwoPhaseGetDummyProc
- * Get the PGPROC that represents 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 */
/************************************************************************/
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;
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);
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;
/*
* 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
+ * 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 inCommit for; see notes there.)
+ * 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);
/* If we crash now, we have prepared: WAL replay will fix things */
- /*
- * Wake up all walsenders to send WAL up to the PREPARE record
- * immediately if replication is enabled
- */
- if (max_wal_senders > 0)
- WalSndWakeup();
-
/* 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
* 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;
}
TwoPhaseFilePath(path, xid);
- fd = BasicOpenFile(path, O_RDONLY | PG_BINARY, 0);
+ fd = OpenTransientFile(path, O_RDONLY | PG_BINARY, 0);
if (fd < 0)
{
if (give_warnings)
*/
if (fstat(fd, &stat))
{
- close(fd);
+ CloseTransientFile(fd);
if (give_warnings)
ereport(WARNING,
(errcode_for_file_access(),
sizeof(pg_crc32)) ||
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);
+ CloseTransientFile(fd);
if (give_warnings)
ereport(WARNING,
(errcode_for_file_access(),
return NULL;
}
- close(fd);
+ CloseTransientFile(fd);
hdr = (TwoPhaseFileHeader *) buf;
if (hdr->magic != TWOPHASE_MAGIC || hdr->total_len != stat.st_size)
FinishPreparedTransaction(const char *gid, bool isCommit)
{
GlobalTransaction gxact;
+ PGPROC *proc;
+ PGXACT *pgxact;
TransactionId xid;
char *buf;
char *bufptr;
* 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
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.)
*/
for (i = 0; i < ndelrels; i++)
{
SMgrRelation srel = smgropen(delrels[i], InvalidBackendId);
- ForkNumber fork;
- for (fork = 0; fork <= MAX_FORKNUM; fork++)
- {
- if (smgrexists(srel, fork))
- smgrdounlink(srel, fork, false);
- }
+ smgrdounlink(srel, false);
smgrclose(srel);
}
* after we send the SI messages. See AtEOXact_Inval()
*/
if (hdr->initfileinval)
- RelationCacheInitFileInvalidate(true);
+ RelationCacheInitFilePreInvalidate();
SendSharedInvalidMessages(invalmsgs, hdr->ninvalmsgs);
if (hdr->initfileinval)
- RelationCacheInitFileInvalidate(false);
+ RelationCacheInitFilePostInvalidate();
/* And now do the callbacks */
if (isCommit)
else
ProcessRecords(bufptr, xid, twophase_postabort_callbacks);
+ PredicateLockTwoPhaseFinish(xid, isCommit);
+
/* Count the prepared xact as committed or aborted */
AtEOXact_PgStat(isCommit);
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.
*/
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",
*
* 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.
*
/*
* 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);
}
}
* the prepared transaction generated xid assignment records. Test
* here must match one used in AssignTransactionId().
*/
- if (InHotStandby && hdr->nsubxacts >= PGPROC_MAX_CACHED_SUBXIDS)
+ if (InHotStandby && (hdr->nsubxacts >= PGPROC_MAX_CACHED_SUBXIDS ||
+ XLogLogicalInfoActive()))
overwriteOK = true;
/*
* 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.
START_CRIT_SECTION();
/* See notes in RecordTransactionCommit */
- MyProc->inCommit = true;
+ MyPgXact->delayChkpt = true;
/* Emit the XLOG commit record */
xlrec.xid = xid;
/* Flush XLOG to disk */
XLogFlush(recptr);
- /*
- * Wake up all walsenders to send WAL up to the COMMIT PREPARED record
- * immediately if replication is enabled
- */
- if (max_wal_senders > 0)
- WalSndWakeup();
-
/* Mark the transaction committed in pg_clog */
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);
}
/*
/* Always flush, since we're about to remove the 2PC state file */
XLogFlush(recptr);
- /*
- * Wake up all walsenders to send WAL up to the ABORT PREPARED record
- * immediately if replication is enabled
- */
- if (max_wal_senders > 0)
- WalSndWakeup();
-
/*
* Mark the transaction aborted in clog. This is not absolutely necessary
* but we may as well do it while we are here.
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);
}