database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-06-26 12:21:12 +03:00
Code Activity

Teach standby conflict resolution to use SIGUSR1

Browse Source 
Conflict reason is passed through directly to the backend, so we can
take decisions about the effect of the conflict based upon the local
state. No specific changes, as yet, though this prepares for later work.
CancelVirtualTransaction() sends signals while holding ProcArrayLock.
Introduce errdetail_abort() to give message detail explaining that the
abort was caused by conflict processing. Remove CONFLICT_MODE states
in favour of using PROCSIG_RECOVERY_CONFLICT states directly, for clarity.
This commit is contained in:
Simon Riggs
2010-01-16 10:05:59 +00:00
parent c9dc53be77
commit a8ce974cdd
11 changed files with 227 additions and 153 deletions
Download Patch File Download Diff File Expand all files Collapse all files

67
src/backend/storage/ipc/standby.c
View File

@ -3,19 +3,15 @@
* standby.c
* Misc functions used in Hot Standby mode.
*
* InitRecoveryTransactionEnvironment()
* ShutdownRecoveryTransactionEnvironment()
*
* ResolveRecoveryConflictWithVirtualXIDs()
*
* All functions for handling RM_STANDBY_ID, which relate to
* AccessExclusiveLocks and starting snapshots for Hot Standby mode.
* Plus conflict recovery processing.
*
* Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/storage/ipc/standby.c,v 1.4 2010/01/14 11:08:02 sriggs Exp $
* $PostgreSQL: pgsql/src/backend/storage/ipc/standby.c,v 1.5 2010/01/16 10:05:50 sriggs Exp $
*
*-------------------------------------------------------------------------
*/
@ -38,7 +34,7 @@ int vacuum_defer_cleanup_age;
static List *RecoveryLockList;
static void ResolveRecoveryConflictWithVirtualXIDs(VirtualTransactionId *waitlist,
char *reason, int cancel_mode);
ProcSignalReason reason);
static void ResolveRecoveryConflictWithLock(Oid dbOid, Oid relOid);
static void LogCurrentRunningXacts(RunningTransactions CurrRunningXacts);
static void LogAccessExclusiveLocks(int nlocks, xl_standby_lock *locks);
@ -162,17 +158,13 @@ WaitExceedsMaxStandbyDelay(void)
* recovery processing. Judgement has already been passed on it within
* a specific rmgr. Here we just issue the orders to the procs. The procs
* then throw the required error as instructed.
*
* We may ask for a specific cancel_mode, typically ERROR or FATAL.
*/
static void
ResolveRecoveryConflictWithVirtualXIDs(VirtualTransactionId *waitlist,
char *reason, int cancel_mode)
ProcSignalReason reason)
{
char waitactivitymsg[100];
Assert(cancel_mode > 0);
while (VirtualTransactionIdIsValid(*waitlist))
{
long wait_s;
@ -206,12 +198,6 @@ ResolveRecoveryConflictWithVirtualXIDs(VirtualTransactionId *waitlist,
len = 100;
memcpy(waitactivitymsg, oldactivitymsg, len);
ereport(trace_recovery(DEBUG5),
(errmsg("virtual transaction %u/%u is blocking %s",
waitlist->backendId,
waitlist->localTransactionId,
reason)));
pgstat_report_waiting(true);
logged = true;
@ -226,40 +212,14 @@ ResolveRecoveryConflictWithVirtualXIDs(VirtualTransactionId *waitlist,
* Now find out who to throw out of the balloon.
*/
Assert(VirtualTransactionIdIsValid(*waitlist));
pid = CancelVirtualTransaction(*waitlist, cancel_mode);
pid = CancelVirtualTransaction(*waitlist, reason);
/*
* Wait awhile for it to die so that we avoid flooding an
* unresponsive backend when system is heavily loaded.
*/
if (pid != 0)
{
/*
* Startup process debug messages
*/
switch (cancel_mode)
{
case CONFLICT_MODE_FATAL:
elog(trace_recovery(DEBUG1),
"recovery disconnects session with pid %ld because of conflict with %s",
(long) pid,
reason);
break;
case CONFLICT_MODE_ERROR:
elog(trace_recovery(DEBUG1),
"recovery cancels virtual transaction %u/%u pid %ld because of conflict with %s",
waitlist->backendId,
waitlist->localTransactionId,
(long) pid,
reason);
break;
default:
/* No conflict pending, so fall through */
break;
}
/*
* Wait awhile for it to die so that we avoid flooding an
* unresponsive backend when system is heavily loaded.
*/
pg_usleep(5000);
}
}
}
@ -285,8 +245,7 @@ ResolveRecoveryConflictWithSnapshot(TransactionId latestRemovedXid)
true);
ResolveRecoveryConflictWithVirtualXIDs(backends,
"snapshot conflict",
CONFLICT_MODE_ERROR);
PROCSIG_RECOVERY_CONFLICT_SNAPSHOT);
}
void
@ -317,8 +276,7 @@ ResolveRecoveryConflictWithTablespace(Oid tsid)
InvalidOid,
false);
ResolveRecoveryConflictWithVirtualXIDs(temp_file_users,
"drop tablespace",
CONFLICT_MODE_ERROR);
PROCSIG_RECOVERY_CONFLICT_TABLESPACE);
}
void
@ -379,8 +337,7 @@ ResolveRecoveryConflictWithLock(Oid dbOid, Oid relOid)
}
ResolveRecoveryConflictWithVirtualXIDs(backends,
"exclusive lock",
CONFLICT_MODE_ERROR);
PROCSIG_RECOVERY_CONFLICT_LOCK);
if (LockAcquireExtended(&locktag, AccessExclusiveLock, true, true, false)
!= LOCKACQUIRE_NOT_AVAIL)