Alvaro Herrera írta:
> Boszormenyi Zoltan wrote:
>
>
>> The vague consensus for syntax options was that the GUC
>> 'lock_timeout' and WAIT [N] extension (wherever NOWAIT
>> is allowed) both should be implemented.
>>
>> Behaviour would be that N seconds timeout should be
>> applied to every lock that the statement would take.
>>
>
> In http://archives.postgresql.org/message-id/291.1242053...@sss.pgh.pa.us
> Tom argues that lock_timeout should be sufficient. I'm not sure what
> does WAIT [N] buy
Okay, we implemented only the lock_timeout GUC.
Patch attached, hopefully in an acceptable form.
Documentation included in the patch, lock_timeout
works the same way as statement_timeout, takes
value in milliseconds and 0 disables the timeout.
Best regards,
Zoltán Böszörményi
--
Bible has answers for everything. Proof:
"But let your communication be, Yea, yea; Nay, nay: for whatsoever is more
than these cometh of evil." (Matthew 5:37) - basics of digital technology.
"May your kingdom come" - superficial description of plate tectonics
----------------------------------
Zoltán Böszörményi
Cybertec Schönig & Schönig GmbH
http://www.postgresql.at/
diff -dcrpN pgsql.orig/doc/src/sgml/config.sgml pgsql/doc/src/sgml/config.sgml
*** pgsql.orig/doc/src/sgml/config.sgml 2009-07-17 07:50:48.000000000 +0200
--- pgsql/doc/src/sgml/config.sgml 2009-07-30 13:12:07.000000000 +0200
*************** COPY postgres_log FROM '/full/path/to/lo
*** 4018,4023 ****
--- 4018,4046 ----
</listitem>
</varlistentry>
+ <varlistentry id="guc-lock-timeout" xreflabel="lock_timeout">
+ <term><varname>lock_timeout</varname> (<type>integer</type>)</term>
+ <indexterm>
+ <primary><varname>lock_timeout</> configuration parameter</primary>
+ </indexterm>
+ <listitem>
+ <para>
+ Abort any statement that tries to lock any rows or tables and the lock
+ has to wait more than the specified number of milliseconds, starting
+ from the time the command arrives at the server from the client.
+ If <varname>log_min_error_statement</> is set to <literal>ERROR</> or
+ lower, the statement that timed out will also be logged.
+ A value of zero (the default) turns off the limitation.
+ </para>
+
+ <para>
+ Setting <varname>lock_timeout</> in
+ <filename>postgresql.conf</> is not recommended because it
+ affects all sessions.
+ </para>
+ </listitem>
+ </varlistentry>
+
<varlistentry id="guc-vacuum-freeze-table-age" xreflabel="vacuum_freeze_table_age">
<term><varname>vacuum_freeze_table_age</varname> (<type>integer</type>)</term>
<indexterm>
diff -dcrpN pgsql.orig/doc/src/sgml/ref/lock.sgml pgsql/doc/src/sgml/ref/lock.sgml
*** pgsql.orig/doc/src/sgml/ref/lock.sgml 2009-01-16 11:44:56.000000000 +0100
--- pgsql/doc/src/sgml/ref/lock.sgml 2009-07-30 13:29:07.000000000 +0200
*************** where <replaceable class="PARAMETER">loc
*** 39,46 ****
<literal>NOWAIT</literal> is specified, <command>LOCK
TABLE</command> does not wait to acquire the desired lock: if it
cannot be acquired immediately, the command is aborted and an
! error is emitted. Once obtained, the lock is held for the
! remainder of the current transaction. (There is no <command>UNLOCK
TABLE</command> command; locks are always released at transaction
end.)
</para>
--- 39,49 ----
<literal>NOWAIT</literal> is specified, <command>LOCK
TABLE</command> does not wait to acquire the desired lock: if it
cannot be acquired immediately, the command is aborted and an
! error is emitted. If <varname>lock_timeout</varname> is set to a value
! higher than 0, and the lock cannot be acquired under the specified
! timeout value in milliseconds, the command is aborted and an error
! is emitted. Once obtained, the lock is held for the remainder of
! the current transaction. (There is no <command>UNLOCK
TABLE</command> command; locks are always released at transaction
end.)
</para>
diff -dcrpN pgsql.orig/doc/src/sgml/ref/select.sgml pgsql/doc/src/sgml/ref/select.sgml
*** pgsql.orig/doc/src/sgml/ref/select.sgml 2009-05-04 11:00:49.000000000 +0200
--- pgsql/doc/src/sgml/ref/select.sgml 2009-07-30 13:36:57.000000000 +0200
*************** FOR SHARE [ OF <replaceable class="param
*** 1101,1106 ****
--- 1101,1114 ----
</para>
<para>
+ If <literal>NOWAIT</> option is not specified and <varname>lock_timeout</varname>
+ is set to a value higher than 0, and the lock needs to wait more than
+ the specified value in milliseconds, the command reports an error after
+ timing out, rather than waiting indefinitely. The note in the previous
+ paragraph applies to the <varname>lock_timeout</varname>, too.
+ </para>
+
+ <para>
<literal>FOR SHARE</literal> behaves similarly, except that it
acquires a shared rather than exclusive lock on each retrieved
row. A shared lock blocks other transactions from performing
diff -dcrpN pgsql.orig/src/backend/access/heap/heapam.c pgsql/src/backend/access/heap/heapam.c
*** pgsql.orig/src/backend/access/heap/heapam.c 2009-06-13 18:24:46.000000000 +0200
--- pgsql/src/backend/access/heap/heapam.c 2009-07-30 12:29:17.000000000 +0200
*************** l3:
*** 3142,3157 ****
*/
if (!have_tuple_lock)
{
if (nowait)
! {
! if (!ConditionalLockTuple(relation, tid, tuple_lock_type))
! ereport(ERROR,
(errcode(ERRCODE_LOCK_NOT_AVAILABLE),
errmsg("could not obtain lock on row in relation \"%s\"",
RelationGetRelationName(relation))));
! }
! else
! LockTuple(relation, tid, tuple_lock_type);
have_tuple_lock = true;
}
--- 3142,3160 ----
*/
if (!have_tuple_lock)
{
+ bool result;
+
if (nowait)
! result = ConditionalLockTuple(relation, tid, tuple_lock_type);
! else
! result = TimedLockTuple(relation, tid, tuple_lock_type);
!
! if (!result)
! ereport(ERROR,
(errcode(ERRCODE_LOCK_NOT_AVAILABLE),
errmsg("could not obtain lock on row in relation \"%s\"",
RelationGetRelationName(relation))));
!
have_tuple_lock = true;
}
*************** l3:
*** 3172,3188 ****
}
else if (infomask & HEAP_XMAX_IS_MULTI)
{
/* wait for multixact to end */
if (nowait)
! {
! if (!ConditionalMultiXactIdWait((MultiXactId) xwait))
! ereport(ERROR,
(errcode(ERRCODE_LOCK_NOT_AVAILABLE),
errmsg("could not obtain lock on row in relation \"%s\"",
RelationGetRelationName(relation))));
- }
- else
- MultiXactIdWait((MultiXactId) xwait);
LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
--- 3175,3191 ----
}
else if (infomask & HEAP_XMAX_IS_MULTI)
{
+ bool result;
/* wait for multixact to end */
if (nowait)
! result = ConditionalMultiXactIdWait((MultiXactId) xwait);
! else
! result = TimedMultiXactIdWait((MultiXactId) xwait);
! if (!result)
! ereport(ERROR,
(errcode(ERRCODE_LOCK_NOT_AVAILABLE),
errmsg("could not obtain lock on row in relation \"%s\"",
RelationGetRelationName(relation))));
LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
*************** l3:
*** 3207,3223 ****
}
else
{
/* wait for regular transaction to end */
if (nowait)
! {
! if (!ConditionalXactLockTableWait(xwait))
! ereport(ERROR,
(errcode(ERRCODE_LOCK_NOT_AVAILABLE),
errmsg("could not obtain lock on row in relation \"%s\"",
RelationGetRelationName(relation))));
- }
- else
- XactLockTableWait(xwait);
LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
--- 3210,3226 ----
}
else
{
+ bool result;
/* wait for regular transaction to end */
if (nowait)
! result = ConditionalXactLockTableWait(xwait);
! else
! result = TimedXactLockTableWait(xwait);
! if (!result)
! ereport(ERROR,
(errcode(ERRCODE_LOCK_NOT_AVAILABLE),
errmsg("could not obtain lock on row in relation \"%s\"",
RelationGetRelationName(relation))));
LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
diff -dcrpN pgsql.orig/src/backend/access/transam/multixact.c pgsql/src/backend/access/transam/multixact.c
*** pgsql.orig/src/backend/access/transam/multixact.c 2009-07-13 11:16:21.000000000 +0200
--- pgsql/src/backend/access/transam/multixact.c 2009-07-30 12:31:18.000000000 +0200
*************** ConditionalMultiXactIdWait(MultiXactId m
*** 636,641 ****
--- 636,678 ----
}
/*
+ * TimedMultiXactIdWait
+ * As above, but only lock if we can get the lock under lock_timeout.
+ */
+ bool
+ TimedMultiXactIdWait(MultiXactId multi)
+ {
+ bool result = true;
+ TransactionId *members;
+ int nmembers;
+
+ nmembers = GetMultiXactIdMembers(multi, &members);
+
+ if (nmembers >= 0)
+ {
+ int i;
+
+ for (i = 0; i < nmembers; i++)
+ {
+ TransactionId member = members[i];
+
+ debug_elog4(DEBUG2, "ConditionalMultiXactIdWait: trying %d (%u)",
+ i, member);
+ if (!TransactionIdIsCurrentTransactionId(member))
+ {
+ result = TimedXactLockTableWait(member);
+ if (!result)
+ break;
+ }
+ }
+
+ pfree(members);
+ }
+
+ return result;
+ }
+
+ /*
* CreateMultiXactId
* Make a new MultiXactId
*
diff -dcrpN pgsql.orig/src/backend/commands/lockcmds.c pgsql/src/backend/commands/lockcmds.c
*** pgsql.orig/src/backend/commands/lockcmds.c 2009-06-13 18:24:48.000000000 +0200
--- pgsql/src/backend/commands/lockcmds.c 2009-07-30 11:09:49.000000000 +0200
*************** LockTableRecurse(Oid reloid, RangeVar *r
*** 65,70 ****
--- 65,71 ----
{
Relation rel;
AclResult aclresult;
+ bool result;
/*
* Acquire the lock. We must do this first to protect against concurrent
*************** LockTableRecurse(Oid reloid, RangeVar *r
*** 72,97 ****
* won't fail.
*/
if (nowait)
{
! if (!ConditionalLockRelationOid(reloid, lockmode))
! {
! /* try to throw error by name; relation could be deleted... */
! char *relname = rv ? rv->relname : get_rel_name(reloid);
! if (relname)
! ereport(ERROR,
(errcode(ERRCODE_LOCK_NOT_AVAILABLE),
errmsg("could not obtain lock on relation \"%s\"",
relname)));
! else
! ereport(ERROR,
(errcode(ERRCODE_LOCK_NOT_AVAILABLE),
errmsg("could not obtain lock on relation with OID %u",
reloid)));
- }
}
- else
- LockRelationOid(reloid, lockmode);
/*
* Now that we have the lock, check to see if the relation really exists
--- 73,97 ----
* won't fail.
*/
if (nowait)
+ result = ConditionalLockRelationOid(reloid, lockmode);
+ else
+ result = TimedLockRelationOid(reloid, lockmode);
+ if (!result)
{
! /* try to throw error by name; relation could be deleted... */
! char *relname = rv ? rv->relname : get_rel_name(reloid);
! if (relname)
! ereport(ERROR,
(errcode(ERRCODE_LOCK_NOT_AVAILABLE),
errmsg("could not obtain lock on relation \"%s\"",
relname)));
! else
! ereport(ERROR,
(errcode(ERRCODE_LOCK_NOT_AVAILABLE),
errmsg("could not obtain lock on relation with OID %u",
reloid)));
}
/*
* Now that we have the lock, check to see if the relation really exists
diff -dcrpN pgsql.orig/src/backend/port/posix_sema.c pgsql/src/backend/port/posix_sema.c
*** pgsql.orig/src/backend/port/posix_sema.c 2009-06-13 18:24:55.000000000 +0200
--- pgsql/src/backend/port/posix_sema.c 2009-07-30 10:37:20.000000000 +0200
***************
*** 24,29 ****
--- 24,30 ----
#include "miscadmin.h"
#include "storage/ipc.h"
#include "storage/pg_sema.h"
+ #include "storage/proc.h" /* for LockTimeout */
#ifdef USE_NAMED_POSIX_SEMAPHORES
*************** PGSemaphoreTryLock(PGSemaphore sema)
*** 313,315 ****
--- 314,359 ----
return true;
}
+
+ /*
+ * PGSemaphoreTimedLock
+ *
+ * Lock a semaphore only if able to do so under the lock_timeout
+ */
+ bool
+ PGSemaphoreTimedLock(PGSemaphore sema, bool interruptOK)
+ {
+ int errStatus;
+ struct timespec timeout;
+
+
+ /*
+ * See notes in sysv_sema.c's implementation of PGSemaphoreLock. Just as
+ * that code does for semop(), we handle both the case where sem_wait()
+ * returns errno == EINTR after a signal, and the case where it just keeps
+ * waiting.
+ */
+ do
+ {
+ ImmediateInterruptOK = interruptOK;
+ CHECK_FOR_INTERRUPTS();
+ if (LockTimeout)
+ {
+ timeout.tv_sec = LockTimeout / 1000;
+ timeout.tv_nsec = (LockTimeout % 1000) * 1000000;
+ errStatus = sem_timedwait(PG_SEM_REF(sema), &timeout);
+ }
+ else
+ errStatus = sem_wait(PG_SEM_REF(sema));
+ ImmediateInterruptOK = false;
+ } while (errStatus < 0 && errno == EINTR);
+
+ if (errStatus < 0)
+ {
+ if (errno == ETIMEDOUT)
+ return false; /* failed to lock it */
+ /* Otherwise we got trouble */
+ elog(FATAL, "sem_wait failed: %m");
+ }
+ return true;
+ }
diff -dcrpN pgsql.orig/src/backend/port/sysv_sema.c pgsql/src/backend/port/sysv_sema.c
*** pgsql.orig/src/backend/port/sysv_sema.c 2009-06-13 18:24:55.000000000 +0200
--- pgsql/src/backend/port/sysv_sema.c 2009-07-30 10:37:37.000000000 +0200
***************
*** 30,35 ****
--- 30,36 ----
#include "miscadmin.h"
#include "storage/ipc.h"
#include "storage/pg_sema.h"
+ #include "storage/proc.h" /* for LockTimeout */
#ifndef HAVE_UNION_SEMUN
*************** PGSemaphoreTryLock(PGSemaphore sema)
*** 497,499 ****
--- 498,590 ----
return true;
}
+
+ /*
+ * PGSemaphoreTimedLock
+ *
+ * Lock a semaphore only if able to do so under the lock_timeout
+ */
+ bool
+ PGSemaphoreTimedLock(PGSemaphore sema, bool interruptOK)
+ {
+ int errStatus;
+ struct sembuf sops;
+ struct timespec timeout;
+
+ sops.sem_op = -1; /* decrement */
+ sops.sem_flg = 0;
+ sops.sem_num = sema->semNum;
+
+ /*
+ * Note: if errStatus is -1 and errno == EINTR then it means we returned
+ * from the operation prematurely because we were sent a signal. So we
+ * try and lock the semaphore again.
+ *
+ * Each time around the loop, we check for a cancel/die interrupt. On
+ * some platforms, if such an interrupt comes in while we are waiting, it
+ * will cause the semop() call to exit with errno == EINTR, allowing us to
+ * service the interrupt (if not in a critical section already) during the
+ * next loop iteration.
+ *
+ * Once we acquire the lock, we do NOT check for an interrupt before
+ * returning. The caller needs to be able to record ownership of the lock
+ * before any interrupt can be accepted.
+ *
+ * There is a window of a few instructions between CHECK_FOR_INTERRUPTS
+ * and entering the semop() call. If a cancel/die interrupt occurs in
+ * that window, we would fail to notice it until after we acquire the lock
+ * (or get another interrupt to escape the semop()). We can avoid this
+ * problem by temporarily setting ImmediateInterruptOK to true before we
+ * do CHECK_FOR_INTERRUPTS; then, a die() interrupt in this interval will
+ * execute directly. However, there is a huge pitfall: there is another
+ * window of a few instructions after the semop() before we are able to
+ * reset ImmediateInterruptOK. If an interrupt occurs then, we'll lose
+ * control, which means that the lock has been acquired but our caller did
+ * not get a chance to record the fact. Therefore, we only set
+ * ImmediateInterruptOK if the caller tells us it's OK to do so, ie, the
+ * caller does not need to record acquiring the lock. (This is currently
+ * true for lockmanager locks, since the process that granted us the lock
+ * did all the necessary state updates. It's not true for SysV semaphores
+ * used to implement LW locks or emulate spinlocks --- but the wait time
+ * for such locks should not be very long, anyway.)
+ *
+ * On some platforms, signals marked SA_RESTART (which is most, for us)
+ * will not interrupt the semop(); it will just keep waiting. Therefore
+ * it's necessary for cancel/die interrupts to be serviced directly by the
+ * signal handler. On these platforms the behavior is really the same
+ * whether the signal arrives just before the semop() begins, or while it
+ * is waiting. The loop on EINTR is thus important only for other types
+ * of interrupts.
+ */
+ do
+ {
+ ImmediateInterruptOK = interruptOK;
+ CHECK_FOR_INTERRUPTS();
+ if (LockTimeout)
+ {
+ timeout.tv_sec = LockTimeout / 1000;
+ timeout.tv_nsec = (LockTimeout % 1000) * 1000000;
+ errStatus = semtimedop(sema->semId, &sops, 1, &timeout);
+ }
+ else
+ errStatus = semop(sema->semId, &sops, 1);
+ ImmediateInterruptOK = false;
+ } while (errStatus < 0 && errno == EINTR);
+
+ if (errStatus < 0)
+ {
+ /* Expect EAGAIN or EWOULDBLOCK (platform-dependent) */
+ #ifdef EAGAIN
+ if (errno == EAGAIN)
+ return false; /* failed to lock it */
+ #endif
+ #if defined(EWOULDBLOCK) && (!defined(EAGAIN) || (EWOULDBLOCK != EAGAIN))
+ if (errno == EWOULDBLOCK)
+ return false; /* failed to lock it */
+ #endif
+ /* Otherwise we got trouble */
+ elog(FATAL, "semop(id=%d) failed: %m", sema->semId);
+ }
+ return true;
+ }
+
diff -dcrpN pgsql.orig/src/backend/port/win32_sema.c pgsql/src/backend/port/win32_sema.c
*** pgsql.orig/src/backend/port/win32_sema.c 2009-06-13 18:24:55.000000000 +0200
--- pgsql/src/backend/port/win32_sema.c 2009-07-30 10:37:57.000000000 +0200
***************
*** 16,21 ****
--- 16,22 ----
#include "miscadmin.h"
#include "storage/ipc.h"
#include "storage/pg_sema.h"
+ #include "storage/proc.h" /* for LockTimeout */
static HANDLE *mySemSet; /* IDs of sema sets acquired so far */
static int numSems; /* number of sema sets acquired so far */
*************** PGSemaphoreTryLock(PGSemaphore sema)
*** 205,207 ****
--- 206,267 ----
/* keep compiler quiet */
return false;
}
+
+ /*
+ * PGSemaphoreTimedLock
+ *
+ * Lock a semaphore only if able to do so under the lock_timeout
+ * Serve the interrupt if interruptOK is true.
+ */
+ bool
+ PGSemaphoreTimedLock(PGSemaphore sema, bool interruptOK)
+ {
+ DWORD ret;
+ HANDLE wh[2];
+
+ wh[0] = *sema;
+ wh[1] = pgwin32_signal_event;
+
+ /*
+ * As in other implementations of PGSemaphoreLock, we need to check for
+ * cancel/die interrupts each time through the loop. But here, there is
+ * no hidden magic about whether the syscall will internally service a
+ * signal --- we do that ourselves.
+ */
+ do
+ {
+ ImmediateInterruptOK = interruptOK;
+ CHECK_FOR_INTERRUPTS();
+
+ errno = 0;
+ ret = WaitForMultipleObjectsEx(2, wh, FALSE, LockTimeout ? LockTimeout : INFINITE, TRUE);
+
+ if (ret == WAIT_OBJECT_0)
+ {
+ /* We got it! */
+ return true;
+ }
+ else if (ret == WAIT_TIMEOUT)
+ {
+ /* Can't get it */
+ errno = EAGAIN;
+ return false;
+ }
+ else if (ret == WAIT_OBJECT_0 + 1)
+ {
+ /* Signal event is set - we have a signal to deliver */
+ pgwin32_dispatch_queued_signals();
+ errno = EINTR;
+ }
+ else
+ /* Otherwise we are in trouble */
+ errno = EIDRM;
+
+ ImmediateInterruptOK = false;
+ } while (errno == EINTR);
+
+ if (errno != 0)
+ ereport(FATAL,
+ (errmsg("could not lock semaphore: error code %d", (int) GetLastError())));
+ }
+
diff -dcrpN pgsql.orig/src/backend/storage/lmgr/lmgr.c pgsql/src/backend/storage/lmgr/lmgr.c
*** pgsql.orig/src/backend/storage/lmgr/lmgr.c 2009-01-02 17:15:28.000000000 +0100
--- pgsql/src/backend/storage/lmgr/lmgr.c 2009-07-30 12:28:44.000000000 +0200
***************
*** 21,26 ****
--- 21,27 ----
#include "catalog/catalog.h"
#include "miscadmin.h"
#include "storage/lmgr.h"
+ #include "storage/proc.h"
#include "storage/procarray.h"
#include "utils/inval.h"
*************** LockRelationOid(Oid relid, LOCKMODE lock
*** 76,82 ****
SetLocktagRelationOid(&tag, relid);
! res = LockAcquire(&tag, lockmode, false, false);
/*
* Now that we have the lock, check for invalidation messages, so that we
--- 77,83 ----
SetLocktagRelationOid(&tag, relid);
! res = LockAcquire(&tag, lockmode, false, false, INFINITE_TIMEOUT);
/*
* Now that we have the lock, check for invalidation messages, so that we
*************** ConditionalLockRelationOid(Oid relid, LO
*** 108,114 ****
SetLocktagRelationOid(&tag, relid);
! res = LockAcquire(&tag, lockmode, false, true);
if (res == LOCKACQUIRE_NOT_AVAIL)
return false;
--- 109,144 ----
SetLocktagRelationOid(&tag, relid);
! res = LockAcquire(&tag, lockmode, false, true, INFINITE_TIMEOUT);
!
! if (res == LOCKACQUIRE_NOT_AVAIL)
! return false;
!
! /*
! * Now that we have the lock, check for invalidation messages; see notes
! * in LockRelationOid.
! */
! if (res != LOCKACQUIRE_ALREADY_HELD)
! AcceptInvalidationMessages();
!
! return true;
! }
!
! /*
! * LockTimeoutRelationOid
! *
! * As LockRelationOid, but only lock if we can under lock_timeout.
! * Returns TRUE iff the lock was acquired.
! */
! bool
! TimedLockRelationOid(Oid relid, LOCKMODE lockmode)
! {
! LOCKTAG tag;
! LockAcquireResult res;
!
! SetLocktagRelationOid(&tag, relid);
!
! res = LockAcquire(&tag, lockmode, false, false, LockTimeout);
if (res == LOCKACQUIRE_NOT_AVAIL)
return false;
*************** LockRelation(Relation relation, LOCKMODE
*** 171,177 ****
relation->rd_lockInfo.lockRelId.dbId,
relation->rd_lockInfo.lockRelId.relId);
! res = LockAcquire(&tag, lockmode, false, false);
/*
* Now that we have the lock, check for invalidation messages; see notes
--- 201,207 ----
relation->rd_lockInfo.lockRelId.dbId,
relation->rd_lockInfo.lockRelId.relId);
! res = LockAcquire(&tag, lockmode, false, false, INFINITE_TIMEOUT);
/*
* Now that we have the lock, check for invalidation messages; see notes
*************** ConditionalLockRelation(Relation relatio
*** 198,204 ****
relation->rd_lockInfo.lockRelId.dbId,
relation->rd_lockInfo.lockRelId.relId);
! res = LockAcquire(&tag, lockmode, false, true);
if (res == LOCKACQUIRE_NOT_AVAIL)
return false;
--- 228,234 ----
relation->rd_lockInfo.lockRelId.dbId,
relation->rd_lockInfo.lockRelId.relId);
! res = LockAcquire(&tag, lockmode, false, true, INFINITE_TIMEOUT);
if (res == LOCKACQUIRE_NOT_AVAIL)
return false;
*************** LockRelationIdForSession(LockRelId *reli
*** 250,256 ****
SET_LOCKTAG_RELATION(tag, relid->dbId, relid->relId);
! (void) LockAcquire(&tag, lockmode, true, false);
}
/*
--- 280,286 ----
SET_LOCKTAG_RELATION(tag, relid->dbId, relid->relId);
! (void) LockAcquire(&tag, lockmode, true, false, INFINITE_TIMEOUT);
}
/*
*************** LockRelationForExtension(Relation relati
*** 285,291 ****
relation->rd_lockInfo.lockRelId.dbId,
relation->rd_lockInfo.lockRelId.relId);
! (void) LockAcquire(&tag, lockmode, false, false);
}
/*
--- 315,321 ----
relation->rd_lockInfo.lockRelId.dbId,
relation->rd_lockInfo.lockRelId.relId);
! (void) LockAcquire(&tag, lockmode, false, false, INFINITE_TIMEOUT);
}
/*
*************** LockPage(Relation relation, BlockNumber
*** 319,325 ****
relation->rd_lockInfo.lockRelId.relId,
blkno);
! (void) LockAcquire(&tag, lockmode, false, false);
}
/*
--- 349,355 ----
relation->rd_lockInfo.lockRelId.relId,
blkno);
! (void) LockAcquire(&tag, lockmode, false, false, INFINITE_TIMEOUT);
}
/*
*************** ConditionalLockPage(Relation relation, B
*** 338,344 ****
relation->rd_lockInfo.lockRelId.relId,
blkno);
! return (LockAcquire(&tag, lockmode, false, true) != LOCKACQUIRE_NOT_AVAIL);
}
/*
--- 368,374 ----
relation->rd_lockInfo.lockRelId.relId,
blkno);
! return (LockAcquire(&tag, lockmode, false, true, INFINITE_TIMEOUT) != LOCKACQUIRE_NOT_AVAIL);
}
/*
*************** LockTuple(Relation relation, ItemPointer
*** 375,381 ****
ItemPointerGetBlockNumber(tid),
ItemPointerGetOffsetNumber(tid));
! (void) LockAcquire(&tag, lockmode, false, false);
}
/*
--- 405,411 ----
ItemPointerGetBlockNumber(tid),
ItemPointerGetOffsetNumber(tid));
! (void) LockAcquire(&tag, lockmode, false, false, INFINITE_TIMEOUT);
}
/*
*************** ConditionalLockTuple(Relation relation,
*** 395,401 ****
ItemPointerGetBlockNumber(tid),
ItemPointerGetOffsetNumber(tid));
! return (LockAcquire(&tag, lockmode, false, true) != LOCKACQUIRE_NOT_AVAIL);
}
/*
--- 425,451 ----
ItemPointerGetBlockNumber(tid),
ItemPointerGetOffsetNumber(tid));
! return (LockAcquire(&tag, lockmode, false, true, INFINITE_TIMEOUT) != LOCKACQUIRE_NOT_AVAIL);
! }
!
! /*
! * TimedLockTuple
! *
! * As above, but only lock if we can get the lock under lock_timeout.
! * Returns TRUE iff the lock was acquired.
! */
! bool
! TimedLockTuple(Relation relation, ItemPointer tid, LOCKMODE lockmode)
! {
! LOCKTAG tag;
!
! SET_LOCKTAG_TUPLE(tag,
! relation->rd_lockInfo.lockRelId.dbId,
! relation->rd_lockInfo.lockRelId.relId,
! ItemPointerGetBlockNumber(tid),
! ItemPointerGetOffsetNumber(tid));
!
! return (LockAcquire(&tag, lockmode, false, false, LockTimeout) != LOCKACQUIRE_NOT_AVAIL);
}
/*
*************** XactLockTableInsert(TransactionId xid)
*** 429,435 ****
SET_LOCKTAG_TRANSACTION(tag, xid);
! (void) LockAcquire(&tag, ExclusiveLock, false, false);
}
/*
--- 479,485 ----
SET_LOCKTAG_TRANSACTION(tag, xid);
! (void) LockAcquire(&tag, ExclusiveLock, false, false, INFINITE_TIMEOUT);
}
/*
*************** XactLockTableWait(TransactionId xid)
*** 473,479 ****
SET_LOCKTAG_TRANSACTION(tag, xid);
! (void) LockAcquire(&tag, ShareLock, false, false);
LockRelease(&tag, ShareLock, false);
--- 523,529 ----
SET_LOCKTAG_TRANSACTION(tag, xid);
! (void) LockAcquire(&tag, ShareLock, false, false, INFINITE_TIMEOUT);
LockRelease(&tag, ShareLock, false);
*************** ConditionalXactLockTableWait(Transaction
*** 501,507 ****
SET_LOCKTAG_TRANSACTION(tag, xid);
! if (LockAcquire(&tag, ShareLock, false, true) == LOCKACQUIRE_NOT_AVAIL)
return false;
LockRelease(&tag, ShareLock, false);
--- 551,589 ----
SET_LOCKTAG_TRANSACTION(tag, xid);
! if (LockAcquire(&tag, ShareLock, false, true, INFINITE_TIMEOUT) == LOCKACQUIRE_NOT_AVAIL)
! return false;
!
! LockRelease(&tag, ShareLock, false);
!
! if (!TransactionIdIsInProgress(xid))
! break;
! xid = SubTransGetParent(xid);
! }
!
! return true;
! }
!
!
! /*
! * TimedXactLockTableWait
! *
! * As above, but only lock if we can get the lock under lock_timeout.
! * Returns TRUE if the lock was acquired.
! */
! bool
! TimedXactLockTableWait(TransactionId xid)
! {
! LOCKTAG tag;
!
! for (;;)
! {
! Assert(TransactionIdIsValid(xid));
! Assert(!TransactionIdEquals(xid, GetTopTransactionIdIfAny()));
!
! SET_LOCKTAG_TRANSACTION(tag, xid);
!
! if (LockAcquire(&tag, ShareLock, false, false, LockTimeout) == LOCKACQUIRE_NOT_AVAIL)
return false;
LockRelease(&tag, ShareLock, false);
*************** VirtualXactLockTableInsert(VirtualTransa
*** 531,537 ****
SET_LOCKTAG_VIRTUALTRANSACTION(tag, vxid);
! (void) LockAcquire(&tag, ExclusiveLock, false, false);
}
/*
--- 613,619 ----
SET_LOCKTAG_VIRTUALTRANSACTION(tag, vxid);
! (void) LockAcquire(&tag, ExclusiveLock, false, false, INFINITE_TIMEOUT);
}
/*
*************** VirtualXactLockTableWait(VirtualTransact
*** 549,555 ****
SET_LOCKTAG_VIRTUALTRANSACTION(tag, vxid);
! (void) LockAcquire(&tag, ShareLock, false, false);
LockRelease(&tag, ShareLock, false);
}
--- 631,637 ----
SET_LOCKTAG_VIRTUALTRANSACTION(tag, vxid);
! (void) LockAcquire(&tag, ShareLock, false, false, INFINITE_TIMEOUT);
LockRelease(&tag, ShareLock, false);
}
*************** ConditionalVirtualXactLockTableWait(Virt
*** 569,575 ****
SET_LOCKTAG_VIRTUALTRANSACTION(tag, vxid);
! if (LockAcquire(&tag, ShareLock, false, true) == LOCKACQUIRE_NOT_AVAIL)
return false;
LockRelease(&tag, ShareLock, false);
--- 651,657 ----
SET_LOCKTAG_VIRTUALTRANSACTION(tag, vxid);
! if (LockAcquire(&tag, ShareLock, false, true, INFINITE_TIMEOUT) == LOCKACQUIRE_NOT_AVAIL)
return false;
LockRelease(&tag, ShareLock, false);
*************** LockDatabaseObject(Oid classid, Oid obji
*** 598,604 ****
objid,
objsubid);
! (void) LockAcquire(&tag, lockmode, false, false);
}
/*
--- 680,686 ----
objid,
objsubid);
! (void) LockAcquire(&tag, lockmode, false, false, INFINITE_TIMEOUT);
}
/*
*************** LockSharedObject(Oid classid, Oid objid,
*** 636,642 ****
objid,
objsubid);
! (void) LockAcquire(&tag, lockmode, false, false);
/* Make sure syscaches are up-to-date with any changes we waited for */
AcceptInvalidationMessages();
--- 718,724 ----
objid,
objsubid);
! (void) LockAcquire(&tag, lockmode, false, false, INFINITE_TIMEOUT);
/* Make sure syscaches are up-to-date with any changes we waited for */
AcceptInvalidationMessages();
*************** LockSharedObjectForSession(Oid classid,
*** 678,684 ****
objid,
objsubid);
! (void) LockAcquire(&tag, lockmode, true, false);
}
/*
--- 760,766 ----
objid,
objsubid);
! (void) LockAcquire(&tag, lockmode, true, false, INFINITE_TIMEOUT);
}
/*
diff -dcrpN pgsql.orig/src/backend/storage/lmgr/lock.c pgsql/src/backend/storage/lmgr/lock.c
*** pgsql.orig/src/backend/storage/lmgr/lock.c 2009-06-13 18:24:57.000000000 +0200
--- pgsql/src/backend/storage/lmgr/lock.c 2009-07-30 14:32:24.000000000 +0200
*************** PROCLOCK_PRINT(const char *where, const
*** 254,260 ****
static uint32 proclock_hash(const void *key, Size keysize);
static void RemoveLocalLock(LOCALLOCK *locallock);
static void GrantLockLocal(LOCALLOCK *locallock, ResourceOwner owner);
! static void WaitOnLock(LOCALLOCK *locallock, ResourceOwner owner);
static bool UnGrantLock(LOCK *lock, LOCKMODE lockmode,
PROCLOCK *proclock, LockMethod lockMethodTable);
static void CleanUpLock(LOCK *lock, PROCLOCK *proclock,
--- 254,261 ----
static uint32 proclock_hash(const void *key, Size keysize);
static void RemoveLocalLock(LOCALLOCK *locallock);
static void GrantLockLocal(LOCALLOCK *locallock, ResourceOwner owner);
! static int WaitOnLock(LOCALLOCK *locallock, ResourceOwner owner,
! int lock_timeout);
static bool UnGrantLock(LOCK *lock, LOCKMODE lockmode,
PROCLOCK *proclock, LockMethod lockMethodTable);
static void CleanUpLock(LOCK *lock, PROCLOCK *proclock,
*************** LockAcquireResult
*** 467,473 ****
LockAcquire(const LOCKTAG *locktag,
LOCKMODE lockmode,
bool sessionLock,
! bool dontWait)
{
LOCKMETHODID lockmethodid = locktag->locktag_lockmethodid;
LockMethod lockMethodTable;
--- 468,475 ----
LockAcquire(const LOCKTAG *locktag,
LOCKMODE lockmode,
bool sessionLock,
! bool dontWait,
! int lock_timeout)
{
LOCKMETHODID lockmethodid = locktag->locktag_lockmethodid;
LockMethod lockMethodTable;
*************** LockAcquire(const LOCKTAG *locktag,
*** 745,750 ****
--- 747,754 ----
}
else
{
+ int wait_result;
+
Assert(status == STATUS_FOUND);
/*
*************** LockAcquire(const LOCKTAG *locktag,
*** 794,800 ****
locktag->locktag_type,
lockmode);
! WaitOnLock(locallock, owner);
TRACE_POSTGRESQL_LOCK_WAIT_DONE(locktag->locktag_field1,
locktag->locktag_field2,
--- 798,804 ----
locktag->locktag_type,
lockmode);
! wait_result = WaitOnLock(locallock, owner, lock_timeout);
TRACE_POSTGRESQL_LOCK_WAIT_DONE(locktag->locktag_field1,
locktag->locktag_field2,
*************** LockAcquire(const LOCKTAG *locktag,
*** 813,818 ****
--- 817,847 ----
* Check the proclock entry status, in case something in the ipc
* communication doesn't work correctly.
*/
+ if (wait_result == STATUS_WAITING)
+ {
+ if (proclock->holdMask == 0)
+ {
+ SHMQueueDelete(&proclock->lockLink);
+ SHMQueueDelete(&proclock->procLink);
+ if (!hash_search_with_hash_value(LockMethodProcLockHash,
+ (void *) &(proclock->tag),
+ proclock_hashcode,
+ HASH_REMOVE,
+ NULL))
+ elog(PANIC, "proclock table corrupted");
+ }
+ else
+ PROCLOCK_PRINT("LockAcquire: TIMED OUT", proclock);
+ lock->nRequested--;
+ lock->requested[lockmode]--;
+ LOCK_PRINT("LockAcquire: TIMED OUT", lock, lockmode);
+ Assert((lock->nRequested > 0) && (lock->requested[lockmode] >= 0));
+ Assert(lock->nGranted <= lock->nRequested);
+ LWLockRelease(partitionLock);
+ if (locallock->nLocks == 0)
+ RemoveLocalLock(locallock);
+ return LOCKACQUIRE_NOT_AVAIL;
+ }
if (!(proclock->holdMask & LOCKBIT_ON(lockmode)))
{
PROCLOCK_PRINT("LockAcquire: INCONSISTENT", proclock);
*************** GrantAwaitedLock(void)
*** 1105,1118 ****
* Caller must have set MyProc->heldLocks to reflect locks already held
* on the lockable object by this process.
*
* The appropriate partition lock must be held at entry.
*/
! static void
! WaitOnLock(LOCALLOCK *locallock, ResourceOwner owner)
{
LOCKMETHODID lockmethodid = LOCALLOCK_LOCKMETHOD(*locallock);
LockMethod lockMethodTable = LockMethods[lockmethodid];
char *volatile new_status = NULL;
LOCK_PRINT("WaitOnLock: sleeping on lock",
locallock->lock, locallock->tag.mode);
--- 1134,1153 ----
* Caller must have set MyProc->heldLocks to reflect locks already held
* on the lockable object by this process.
*
+ * Result: (returns value of ProcSleep())
+ * STATUS_OK if we acquired the lock
+ * STATUS_ERROR if not (deadlock)
+ * STATUS_WAITING if not (timeout)
+ *
* The appropriate partition lock must be held at entry.
*/
! static int
! WaitOnLock(LOCALLOCK *locallock, ResourceOwner owner, int lock_timeout)
{
LOCKMETHODID lockmethodid = LOCALLOCK_LOCKMETHOD(*locallock);
LockMethod lockMethodTable = LockMethods[lockmethodid];
char *volatile new_status = NULL;
+ int wait_status;
LOCK_PRINT("WaitOnLock: sleeping on lock",
locallock->lock, locallock->tag.mode);
*************** WaitOnLock(LOCALLOCK *locallock, Resourc
*** 1154,1161 ****
*/
PG_TRY();
{
! if (ProcSleep(locallock, lockMethodTable) != STATUS_OK)
{
/*
* We failed as a result of a deadlock, see CheckDeadLock(). Quit
* now.
--- 1189,1208 ----
*/
PG_TRY();
{
! wait_status = ProcSleep(locallock, lockMethodTable, lock_timeout);
! switch (wait_status)
{
+ case STATUS_OK:
+ /* Got lock */
+ break;
+ case STATUS_WAITING:
+ /*
+ * We failed as a result of a timeout. Quit now.
+ */
+ LOCK_PRINT("WaitOnLock: timeout on lock",
+ locallock->lock, locallock->tag.mode);
+ break;
+ default:
/*
* We failed as a result of a deadlock, see CheckDeadLock(). Quit
* now.
*************** WaitOnLock(LOCALLOCK *locallock, Resourc
*** 1202,1207 ****
--- 1249,1256 ----
LOCK_PRINT("WaitOnLock: wakeup on lock",
locallock->lock, locallock->tag.mode);
+
+ return wait_status;
}
/*
diff -dcrpN pgsql.orig/src/backend/storage/lmgr/lwlock.c pgsql/src/backend/storage/lmgr/lwlock.c
*** pgsql.orig/src/backend/storage/lmgr/lwlock.c 2009-01-02 17:15:28.000000000 +0100
--- pgsql/src/backend/storage/lmgr/lwlock.c 2009-07-30 10:45:39.000000000 +0200
*************** LWLockConditionalAcquire(LWLockId lockid
*** 554,559 ****
--- 554,756 ----
}
/*
+ * LWLockTimedAcquire - acquire a lightweight lock in the specified mode
+ *
+ * If the lock is not available, sleep until it is or until lock_timeout
+ * whichever is sooner
+ *
+ * Side effect: cancel/die interrupts are held off until lock release.
+ */
+ bool
+ LWLockTimedAcquire(LWLockId lockid, LWLockMode mode)
+ {
+ volatile LWLock *lock = &(LWLockArray[lockid].lock);
+ PGPROC *proc = MyProc;
+ bool retry = false;
+ int extraWaits = 0;
+ bool timeout;
+
+ PRINT_LWDEBUG("LWLockAcquire", lockid, lock);
+
+ #ifdef LWLOCK_STATS
+ /* Set up local count state first time through in a given process */
+ if (counts_for_pid != MyProcPid)
+ {
+ int *LWLockCounter = (int *) ((char *) LWLockArray - 2 * sizeof(int));
+ int numLocks = LWLockCounter[1];
+
+ sh_acquire_counts = calloc(numLocks, sizeof(int));
+ ex_acquire_counts = calloc(numLocks, sizeof(int));
+ block_counts = calloc(numLocks, sizeof(int));
+ counts_for_pid = MyProcPid;
+ on_shmem_exit(print_lwlock_stats, 0);
+ }
+ /* Count lock acquisition attempts */
+ if (mode == LW_EXCLUSIVE)
+ ex_acquire_counts[lockid]++;
+ else
+ sh_acquire_counts[lockid]++;
+ #endif /* LWLOCK_STATS */
+
+ /*
+ * We can't wait if we haven't got a PGPROC. This should only occur
+ * during bootstrap or shared memory initialization. Put an Assert here
+ * to catch unsafe coding practices.
+ */
+ Assert(!(proc == NULL && IsUnderPostmaster));
+
+ /* Ensure we will have room to remember the lock */
+ if (num_held_lwlocks >= MAX_SIMUL_LWLOCKS)
+ elog(ERROR, "too many LWLocks taken");
+
+ /*
+ * Lock out cancel/die interrupts until we exit the code section protected
+ * by the LWLock. This ensures that interrupts will not interfere with
+ * manipulations of data structures in shared memory.
+ */
+ HOLD_INTERRUPTS();
+
+ /*
+ * Loop here to try to acquire lock after each time we are signaled by
+ * LWLockRelease.
+ *
+ * NOTE: it might seem better to have LWLockRelease actually grant us the
+ * lock, rather than retrying and possibly having to go back to sleep. But
+ * in practice that is no good because it means a process swap for every
+ * lock acquisition when two or more processes are contending for the same
+ * lock. Since LWLocks are normally used to protect not-very-long
+ * sections of computation, a process needs to be able to acquire and
+ * release the same lock many times during a single CPU time slice, even
+ * in the presence of contention. The efficiency of being able to do that
+ * outweighs the inefficiency of sometimes wasting a process dispatch
+ * cycle because the lock is not free when a released waiter finally gets
+ * to run. See pgsql-hackers archives for 29-Dec-01.
+ */
+ for (;;)
+ {
+ bool mustwait;
+
+ /* Acquire mutex. Time spent holding mutex should be short! */
+ SpinLockAcquire(&lock->mutex);
+
+ /* If retrying, allow LWLockRelease to release waiters again */
+ if (retry)
+ lock->releaseOK = true;
+
+ /* If I can get the lock, do so quickly. */
+ if (mode == LW_EXCLUSIVE)
+ {
+ if (lock->exclusive == 0 && lock->shared == 0)
+ {
+ lock->exclusive++;
+ mustwait = false;
+ }
+ else
+ mustwait = true;
+ }
+ else
+ {
+ if (lock->exclusive == 0)
+ {
+ lock->shared++;
+ mustwait = false;
+ }
+ else
+ mustwait = true;
+ }
+
+ if (!mustwait)
+ break; /* got the lock */
+
+ /*
+ * Add myself to wait queue.
+ *
+ * If we don't have a PGPROC structure, there's no way to wait. This
+ * should never occur, since MyProc should only be null during shared
+ * memory initialization.
+ */
+ if (proc == NULL)
+ elog(PANIC, "cannot wait without a PGPROC structure");
+
+ proc->lwWaiting = true;
+ proc->lwExclusive = (mode == LW_EXCLUSIVE);
+ proc->lwWaitLink = NULL;
+ if (lock->head == NULL)
+ lock->head = proc;
+ else
+ lock->tail->lwWaitLink = proc;
+ lock->tail = proc;
+
+ /* Can release the mutex now */
+ SpinLockRelease(&lock->mutex);
+
+ /*
+ * Wait until awakened.
+ *
+ * Since we share the process wait semaphore with the regular lock
+ * manager and ProcWaitForSignal, and we may need to acquire an LWLock
+ * while one of those is pending, it is possible that we get awakened
+ * for a reason other than being signaled by LWLockRelease. If so,
+ * loop back and wait again. Once we've gotten the LWLock,
+ * re-increment the sema by the number of additional signals received,
+ * so that the lock manager or signal manager will see the received
+ * signal when it next waits.
+ */
+ LOG_LWDEBUG("LWLockAcquire", lockid, "waiting");
+
+ #ifdef LWLOCK_STATS
+ block_counts[lockid]++;
+ #endif
+
+ TRACE_POSTGRESQL_LWLOCK_WAIT_START(lockid, mode);
+
+ for (;;)
+ {
+ /* "false" means cannot accept cancel/die interrupt here. */
+ timeout = !PGSemaphoreTimedLock(&proc->sem, false);
+ if (timeout)
+ break;
+ if (!proc->lwWaiting)
+ break;
+ extraWaits++;
+ }
+
+ TRACE_POSTGRESQL_LWLOCK_WAIT_DONE(lockid, mode);
+
+ if (timeout)
+ {
+ LOG_LWDEBUG("LWLockTimedAcquire", lockid, "timed out");
+ break;
+ }
+
+ LOG_LWDEBUG("LWLockTimedAcquire", lockid, "awakened");
+
+ /* Now loop back and try to acquire lock again. */
+ retry = true;
+ }
+
+ /* We are done updating shared state of the lock itself. */
+ SpinLockRelease(&lock->mutex);
+
+ if (timeout)
+ goto out;
+
+ TRACE_POSTGRESQL_LWLOCK_ACQUIRE(lockid, mode);
+
+ /* Add lock to list of locks held by this backend */
+ held_lwlocks[num_held_lwlocks++] = lockid;
+
+ out:
+ /*
+ * Fix the process wait semaphore's count for any absorbed wakeups.
+ */
+ while (extraWaits-- > 0)
+ PGSemaphoreUnlock(&proc->sem);
+
+ return !timeout;
+ }
+
+ /*
* LWLockRelease - release a previously acquired lock
*/
void
diff -dcrpN pgsql.orig/src/backend/storage/lmgr/proc.c pgsql/src/backend/storage/lmgr/proc.c
*** pgsql.orig/src/backend/storage/lmgr/proc.c 2009-06-13 18:24:57.000000000 +0200
--- pgsql/src/backend/storage/lmgr/proc.c 2009-07-30 11:35:54.000000000 +0200
***************
*** 50,55 ****
--- 50,56 ----
/* GUC variables */
int DeadlockTimeout = 1000;
int StatementTimeout = 0;
+ int LockTimeout = 0;
bool log_lock_waits = false;
/* Pointer to this process's PGPROC struct, if any */
*************** ProcQueueInit(PROC_QUEUE *queue)
*** 717,723 ****
* The lock table's partition lock must be held at entry, and will be held
* at exit.
*
! * Result: STATUS_OK if we acquired the lock, STATUS_ERROR if not (deadlock).
*
* ASSUME: that no one will fiddle with the queue until after
* we release the partition lock.
--- 718,727 ----
* The lock table's partition lock must be held at entry, and will be held
* at exit.
*
! * Result:
! * STATUS_OK if we acquired the lock
! * STATUS_ERROR if not (deadlock)
! * STATUS_WAITING if not (timeout)
*
* ASSUME: that no one will fiddle with the queue until after
* we release the partition lock.
*************** ProcQueueInit(PROC_QUEUE *queue)
*** 728,734 ****
* semaphore is normally zero, so when we try to acquire it, we sleep.
*/
int
! ProcSleep(LOCALLOCK *locallock, LockMethod lockMethodTable)
{
LOCKMODE lockmode = locallock->tag.mode;
LOCK *lock = locallock->lock;
--- 732,738 ----
* semaphore is normally zero, so when we try to acquire it, we sleep.
*/
int
! ProcSleep(LOCALLOCK *locallock, LockMethod lockMethodTable, int lock_timeout)
{
LOCKMODE lockmode = locallock->tag.mode;
LOCK *lock = locallock->lock;
*************** ProcSleep(LOCALLOCK *locallock, LockMeth
*** 889,895 ****
*/
do
{
! PGSemaphoreLock(&MyProc->sem, true);
/*
* waitStatus could change from STATUS_WAITING to something else
--- 893,902 ----
*/
do
{
! if (lock_timeout == INFINITE_TIMEOUT)
! PGSemaphoreLock(&MyProc->sem, true);
! else if (!PGSemaphoreTimedLock(&MyProc->sem, true))
! break;
/*
* waitStatus could change from STATUS_WAITING to something else
*************** ProcSleep(LOCALLOCK *locallock, LockMeth
*** 906,912 ****
{
PGPROC *autovac = GetBlockingAutoVacuumPgproc();
! LWLockAcquire(ProcArrayLock, LW_EXCLUSIVE);
/*
* Only do it if the worker is not working to protect against Xid
--- 913,922 ----
{
PGPROC *autovac = GetBlockingAutoVacuumPgproc();
! if (lock_timeout == INFINITE_TIMEOUT)
! LWLockAcquire(ProcArrayLock, LW_EXCLUSIVE);
! else if (!LWLockTimedAcquire(ProcArrayLock, LW_EXCLUSIVE))
! break;
/*
* Only do it if the worker is not working to protect against Xid
diff -dcrpN pgsql.orig/src/backend/utils/adt/lockfuncs.c pgsql/src/backend/utils/adt/lockfuncs.c
*** pgsql.orig/src/backend/utils/adt/lockfuncs.c 2009-01-02 17:15:30.000000000 +0100
--- pgsql/src/backend/utils/adt/lockfuncs.c 2009-07-30 11:40:19.000000000 +0200
*************** pg_advisory_lock_int8(PG_FUNCTION_ARGS)
*** 337,343 ****
SET_LOCKTAG_INT64(tag, key);
! (void) LockAcquire(&tag, ExclusiveLock, true, false);
PG_RETURN_VOID();
}
--- 337,343 ----
SET_LOCKTAG_INT64(tag, key);
! (void) LockAcquire(&tag, ExclusiveLock, true, false, INFINITE_TIMEOUT);
PG_RETURN_VOID();
}
*************** pg_advisory_lock_shared_int8(PG_FUNCTION
*** 353,359 ****
SET_LOCKTAG_INT64(tag, key);
! (void) LockAcquire(&tag, ShareLock, true, false);
PG_RETURN_VOID();
}
--- 353,359 ----
SET_LOCKTAG_INT64(tag, key);
! (void) LockAcquire(&tag, ShareLock, true, false, INFINITE_TIMEOUT);
PG_RETURN_VOID();
}
*************** pg_try_advisory_lock_int8(PG_FUNCTION_AR
*** 372,378 ****
SET_LOCKTAG_INT64(tag, key);
! res = LockAcquire(&tag, ExclusiveLock, true, true);
PG_RETURN_BOOL(res != LOCKACQUIRE_NOT_AVAIL);
}
--- 372,378 ----
SET_LOCKTAG_INT64(tag, key);
! res = LockAcquire(&tag, ExclusiveLock, true, true, INFINITE_TIMEOUT);
PG_RETURN_BOOL(res != LOCKACQUIRE_NOT_AVAIL);
}
*************** pg_try_advisory_lock_shared_int8(PG_FUNC
*** 391,397 ****
SET_LOCKTAG_INT64(tag, key);
! res = LockAcquire(&tag, ShareLock, true, true);
PG_RETURN_BOOL(res != LOCKACQUIRE_NOT_AVAIL);
}
--- 391,397 ----
SET_LOCKTAG_INT64(tag, key);
! res = LockAcquire(&tag, ShareLock, true, true, INFINITE_TIMEOUT);
PG_RETURN_BOOL(res != LOCKACQUIRE_NOT_AVAIL);
}
*************** pg_advisory_lock_int4(PG_FUNCTION_ARGS)
*** 446,452 ****
SET_LOCKTAG_INT32(tag, key1, key2);
! (void) LockAcquire(&tag, ExclusiveLock, true, false);
PG_RETURN_VOID();
}
--- 446,452 ----
SET_LOCKTAG_INT32(tag, key1, key2);
! (void) LockAcquire(&tag, ExclusiveLock, true, false, INFINITE_TIMEOUT);
PG_RETURN_VOID();
}
*************** pg_advisory_lock_shared_int4(PG_FUNCTION
*** 463,469 ****
SET_LOCKTAG_INT32(tag, key1, key2);
! (void) LockAcquire(&tag, ShareLock, true, false);
PG_RETURN_VOID();
}
--- 463,469 ----
SET_LOCKTAG_INT32(tag, key1, key2);
! (void) LockAcquire(&tag, ShareLock, true, false, INFINITE_TIMEOUT);
PG_RETURN_VOID();
}
*************** pg_try_advisory_lock_int4(PG_FUNCTION_AR
*** 483,489 ****
SET_LOCKTAG_INT32(tag, key1, key2);
! res = LockAcquire(&tag, ExclusiveLock, true, true);
PG_RETURN_BOOL(res != LOCKACQUIRE_NOT_AVAIL);
}
--- 483,489 ----
SET_LOCKTAG_INT32(tag, key1, key2);
! res = LockAcquire(&tag, ExclusiveLock, true, true, INFINITE_TIMEOUT);
PG_RETURN_BOOL(res != LOCKACQUIRE_NOT_AVAIL);
}
*************** pg_try_advisory_lock_shared_int4(PG_FUNC
*** 503,509 ****
SET_LOCKTAG_INT32(tag, key1, key2);
! res = LockAcquire(&tag, ShareLock, true, true);
PG_RETURN_BOOL(res != LOCKACQUIRE_NOT_AVAIL);
}
--- 503,509 ----
SET_LOCKTAG_INT32(tag, key1, key2);
! res = LockAcquire(&tag, ShareLock, true, true, INFINITE_TIMEOUT);
PG_RETURN_BOOL(res != LOCKACQUIRE_NOT_AVAIL);
}
diff -dcrpN pgsql.orig/src/backend/utils/misc/guc.c pgsql/src/backend/utils/misc/guc.c
*** pgsql.orig/src/backend/utils/misc/guc.c 2009-07-23 14:40:12.000000000 +0200
--- pgsql/src/backend/utils/misc/guc.c 2009-07-30 10:08:25.000000000 +0200
*************** static struct config_int ConfigureNamesI
*** 1539,1544 ****
--- 1539,1554 ----
},
{
+ {"lock_timeout", PGC_USERSET, CLIENT_CONN_STATEMENT,
+ gettext_noop("Sets the maximum allowed timeout for any lock taken by a statement."),
+ gettext_noop("A value of 0 turns off the timeout."),
+ GUC_UNIT_MS
+ },
+ &LockTimeout,
+ 0, 0, INT_MAX, NULL, NULL
+ },
+
+ {
{"vacuum_freeze_min_age", PGC_USERSET, CLIENT_CONN_STATEMENT,
gettext_noop("Minimum age at which VACUUM should freeze a table row."),
NULL
diff -dcrpN pgsql.orig/src/include/access/multixact.h pgsql/src/include/access/multixact.h
*** pgsql.orig/src/include/access/multixact.h 2009-01-02 17:15:37.000000000 +0100
--- pgsql/src/include/access/multixact.h 2009-07-30 12:25:55.000000000 +0200
*************** extern bool MultiXactIdIsRunning(MultiXa
*** 48,53 ****
--- 48,54 ----
extern bool MultiXactIdIsCurrent(MultiXactId multi);
extern void MultiXactIdWait(MultiXactId multi);
extern bool ConditionalMultiXactIdWait(MultiXactId multi);
+ extern bool TimedMultiXactIdWait(MultiXactId multi);
extern void MultiXactIdSetOldestMember(void);
extern int GetMultiXactIdMembers(MultiXactId multi, TransactionId **xids);
diff -dcrpN pgsql.orig/src/include/storage/lmgr.h pgsql/src/include/storage/lmgr.h
*** pgsql.orig/src/include/storage/lmgr.h 2009-06-13 18:25:05.000000000 +0200
--- pgsql/src/include/storage/lmgr.h 2009-07-30 12:25:19.000000000 +0200
*************** extern void RelationInitLockInfo(Relatio
*** 25,30 ****
--- 25,31 ----
/* Lock a relation */
extern void LockRelationOid(Oid relid, LOCKMODE lockmode);
extern bool ConditionalLockRelationOid(Oid relid, LOCKMODE lockmode);
+ extern bool TimedLockRelationOid(Oid relid, LOCKMODE lockmode);
extern void UnlockRelationId(LockRelId *relid, LOCKMODE lockmode);
extern void UnlockRelationOid(Oid relid, LOCKMODE lockmode);
*************** extern void UnlockPage(Relation relation
*** 48,53 ****
--- 49,56 ----
extern void LockTuple(Relation relation, ItemPointer tid, LOCKMODE lockmode);
extern bool ConditionalLockTuple(Relation relation, ItemPointer tid,
LOCKMODE lockmode);
+ extern bool TimedLockTuple(Relation relation, ItemPointer tid,
+ LOCKMODE lockmode);
extern void UnlockTuple(Relation relation, ItemPointer tid, LOCKMODE lockmode);
/* Lock an XID (used to wait for a transaction to finish) */
*************** extern void XactLockTableInsert(Transact
*** 55,60 ****
--- 58,64 ----
extern void XactLockTableDelete(TransactionId xid);
extern void XactLockTableWait(TransactionId xid);
extern bool ConditionalXactLockTableWait(TransactionId xid);
+ extern bool TimedXactLockTableWait(TransactionId xid);
/* Lock a VXID (used to wait for a transaction to finish) */
extern void VirtualXactLockTableInsert(VirtualTransactionId vxid);
diff -dcrpN pgsql.orig/src/include/storage/lock.h pgsql/src/include/storage/lock.h
*** pgsql.orig/src/include/storage/lock.h 2009-04-14 10:28:46.000000000 +0200
--- pgsql/src/include/storage/lock.h 2009-07-30 11:28:44.000000000 +0200
*************** extern uint32 LockTagHashCode(const LOCK
*** 476,482 ****
extern LockAcquireResult LockAcquire(const LOCKTAG *locktag,
LOCKMODE lockmode,
bool sessionLock,
! bool dontWait);
extern bool LockRelease(const LOCKTAG *locktag,
LOCKMODE lockmode, bool sessionLock);
extern void LockReleaseAll(LOCKMETHODID lockmethodid, bool allLocks);
--- 476,483 ----
extern LockAcquireResult LockAcquire(const LOCKTAG *locktag,
LOCKMODE lockmode,
bool sessionLock,
! bool dontWait,
! int lock_timeout);
extern bool LockRelease(const LOCKTAG *locktag,
LOCKMODE lockmode, bool sessionLock);
extern void LockReleaseAll(LOCKMETHODID lockmethodid, bool allLocks);
diff -dcrpN pgsql.orig/src/include/storage/lwlock.h pgsql/src/include/storage/lwlock.h
*** pgsql.orig/src/include/storage/lwlock.h 2009-03-04 10:27:30.000000000 +0100
--- pgsql/src/include/storage/lwlock.h 2009-07-30 11:36:44.000000000 +0200
*************** extern bool Trace_lwlocks;
*** 92,97 ****
--- 92,98 ----
extern LWLockId LWLockAssign(void);
extern void LWLockAcquire(LWLockId lockid, LWLockMode mode);
extern bool LWLockConditionalAcquire(LWLockId lockid, LWLockMode mode);
+ extern bool LWLockTimedAcquire(LWLockId lockid, LWLockMode mode);
extern void LWLockRelease(LWLockId lockid);
extern void LWLockReleaseAll(void);
extern bool LWLockHeldByMe(LWLockId lockid);
diff -dcrpN pgsql.orig/src/include/storage/pg_sema.h pgsql/src/include/storage/pg_sema.h
*** pgsql.orig/src/include/storage/pg_sema.h 2009-01-02 17:15:39.000000000 +0100
--- pgsql/src/include/storage/pg_sema.h 2009-07-30 10:36:19.000000000 +0200
*************** extern void PGSemaphoreUnlock(PGSemaphor
*** 80,83 ****
--- 80,86 ----
/* Lock a semaphore only if able to do so without blocking */
extern bool PGSemaphoreTryLock(PGSemaphore sema);
+ /* Lock a semaphore only if able to do so under the lock_timeout */
+ extern bool PGSemaphoreTimedLock(PGSemaphore sema, bool interruptOK);
+
#endif /* PG_SEMA_H */
diff -dcrpN pgsql.orig/src/include/storage/proc.h pgsql/src/include/storage/proc.h
*** pgsql.orig/src/include/storage/proc.h 2009-02-26 12:23:28.000000000 +0100
--- pgsql/src/include/storage/proc.h 2009-07-30 11:15:01.000000000 +0200
*************** typedef struct PROC_HDR
*** 146,155 ****
--- 146,158 ----
*/
#define NUM_AUXILIARY_PROCS 3
+ /* For checking LockTimeout */
+ #define INFINITE_TIMEOUT 0
/* configurable options */
extern int DeadlockTimeout;
extern int StatementTimeout;
+ extern int LockTimeout;
extern bool log_lock_waits;
extern volatile bool cancel_from_timeout;
*************** extern bool HaveNFreeProcs(int n);
*** 168,174 ****
extern void ProcReleaseLocks(bool isCommit);
extern void ProcQueueInit(PROC_QUEUE *queue);
! extern int ProcSleep(LOCALLOCK *locallock, LockMethod lockMethodTable);
extern PGPROC *ProcWakeup(PGPROC *proc, int waitStatus);
extern void ProcLockWakeup(LockMethod lockMethodTable, LOCK *lock);
extern void LockWaitCancel(void);
--- 171,177 ----
extern void ProcReleaseLocks(bool isCommit);
extern void ProcQueueInit(PROC_QUEUE *queue);
! extern int ProcSleep(LOCALLOCK *locallock, LockMethod lockMethodTable, int lock_timeout);
extern PGPROC *ProcWakeup(PGPROC *proc, int waitStatus);
extern void ProcLockWakeup(LockMethod lockMethodTable, LOCK *lock);
extern void LockWaitCancel(void);
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