static void ResolveRecoveryConflictWithVirtualXIDs(VirtualTransactionId *waitlist,
ProcSignalReason reason);
-static void ResolveRecoveryConflictWithLock(Oid dbOid, Oid relOid);
static void SendRecoveryConflictWithBufferPin(ProcSignalReason reason);
static XLogRecPtr LogCurrentRunningXacts(RunningTransactions CurrRunningXacts);
static void LogAccessExclusiveLocks(int nlocks, xl_standby_lock *locks);
}
}
-static void
-ResolveRecoveryConflictWithLock(Oid dbOid, Oid relOid)
+/*
+ * ResolveRecoveryConflictWithLock is called from ProcSleep()
+ * to resolve conflicts with other backends holding relation locks.
+ *
+ * The WaitLatch sleep normally done in ProcSleep()
+ * (when not InHotStandby) is performed here, for code clarity.
+ *
+ * We either resolve conflicts immediately or set a timeout to wake us at
+ * the limit of our patience.
+ *
+ * Resolve conflicts by cancelling to all backends holding a conflicting
+ * lock. As we are already queued to be granted the lock, no new lock
+ * requests conflicting with ours will be granted in the meantime.
+ *
+ * Deadlocks involving the Startup process and an ordinary backend process
+ * will be detected by the deadlock detector within the ordinary backend.
+ */
+void
+ResolveRecoveryConflictWithLock(LOCKTAG locktag)
{
- VirtualTransactionId *backends;
- bool lock_acquired = false;
- int num_attempts = 0;
- LOCKTAG locktag;
+ TimestampTz ltime;
- SET_LOCKTAG_RELATION(locktag, dbOid, relOid);
+ Assert(InHotStandby);
- /*
- * If blowing away everybody with conflicting locks doesn't work, after
- * the first two attempts then we just start blowing everybody away until
- * it does work. We do this because its likely that we either have too
- * many locks and we just can't get one at all, or that there are many
- * people crowding for the same table. Recovery must win; the end
- * justifies the means.
- */
- while (!lock_acquired)
- {
- if (++num_attempts < 3)
- backends = GetLockConflicts(&locktag, AccessExclusiveLock);
- else
- backends = GetConflictingVirtualXIDs(InvalidTransactionId,
- InvalidOid);
+ ltime = GetStandbyLimitTime();
+ if (GetCurrentTimestamp() >= ltime)
+ {
+ /*
+ * We're already behind, so clear a path as quickly as possible.
+ */
+ VirtualTransactionId *backends;
+ backends = GetLockConflicts(&locktag, AccessExclusiveLock);
ResolveRecoveryConflictWithVirtualXIDs(backends,
PROCSIG_RECOVERY_CONFLICT_LOCK);
+ }
+ else
+ {
+ /*
+ * Wait (or wait again) until ltime
+ */
+ EnableTimeoutParams timeouts[1];
- if (LockAcquireExtended(&locktag, AccessExclusiveLock, true, true, false)
- != LOCKACQUIRE_NOT_AVAIL)
- lock_acquired = true;
+ timeouts[0].id = STANDBY_LOCK_TIMEOUT;
+ timeouts[0].type = TMPARAM_AT;
+ timeouts[0].fin_time = ltime;
+ enable_timeouts(timeouts, 1);
}
+
+ /* Wait to be signaled by the release of the Relation Lock */
+ ProcWaitForSignal();
+
+ /*
+ * Clear any timeout requests established above. We assume here that the
+ * Startup process doesn't have any other outstanding timeouts than those
+ * used by this function. If that stops being true, we could cancel the
+ * timeouts individually, but that'd be slower.
+ */
+ disable_all_timeouts(false);
}
/*
SendRecoveryConflictWithBufferPin(PROCSIG_RECOVERY_CONFLICT_BUFFERPIN);
}
+/*
+ * StandbyLockTimeoutHandler() will be called if STANDBY_LOCK_TIMEOUT is exceeded.
+ * This doesn't need to do anything, simply waking up is enough.
+ */
+void
+StandbyLockTimeoutHandler(void)
+{
+}
/*
* -----------------------------------------------------
* process is the proxy by which the original locks are implemented.
*
* We only keep track of AccessExclusiveLocks, which are only ever held by
- * one transaction on one relation, and don't worry about lock queuing.
+ * one transaction on one relation.
*
* We keep a single dynamically expandible list of locks in local memory,
* RelationLockList, so we can keep track of the various entries made by
newlock->relOid = relOid;
RecoveryLockList = lappend(RecoveryLockList, newlock);
- /*
- * Attempt to acquire the lock as requested, if not resolve conflict
- */
SET_LOCKTAG_RELATION(locktag, newlock->dbOid, newlock->relOid);
- if (LockAcquireExtended(&locktag, AccessExclusiveLock, true, true, false)
- == LOCKACQUIRE_NOT_AVAIL)
- ResolveRecoveryConflictWithLock(newlock->dbOid, newlock->relOid);
+ LockAcquireExtended(&locktag, AccessExclusiveLock, true, false, false);
}
static void
#include "postmaster/autovacuum.h"
#include "replication/slot.h"
#include "replication/syncrep.h"
+#include "storage/standby.h"
#include "storage/ipc.h"
#include "storage/lmgr.h"
#include "storage/pmsignal.h"
*
* If LockTimeout is set, also enable the timeout for that. We can save a
* few cycles by enabling both timeout sources in one call.
+ *
+ * If InHotStandby we set lock waits slightly later for clarity with other
+ * code.
*/
- if (LockTimeout > 0)
+ if (!InHotStandby)
{
- EnableTimeoutParams timeouts[2];
-
- timeouts[0].id = DEADLOCK_TIMEOUT;
- timeouts[0].type = TMPARAM_AFTER;
- timeouts[0].delay_ms = DeadlockTimeout;
- timeouts[1].id = LOCK_TIMEOUT;
- timeouts[1].type = TMPARAM_AFTER;
- timeouts[1].delay_ms = LockTimeout;
- enable_timeouts(timeouts, 2);
+ if (LockTimeout > 0)
+ {
+ EnableTimeoutParams timeouts[2];
+
+ timeouts[0].id = DEADLOCK_TIMEOUT;
+ timeouts[0].type = TMPARAM_AFTER;
+ timeouts[0].delay_ms = DeadlockTimeout;
+ timeouts[1].id = LOCK_TIMEOUT;
+ timeouts[1].type = TMPARAM_AFTER;
+ timeouts[1].delay_ms = LockTimeout;
+ enable_timeouts(timeouts, 2);
+ }
+ else
+ enable_timeout_after(DEADLOCK_TIMEOUT, DeadlockTimeout);
}
- else
- enable_timeout_after(DEADLOCK_TIMEOUT, DeadlockTimeout);
/*
* If somebody wakes us between LWLockRelease and WaitLatch, the latch
*/
do
{
- WaitLatch(MyLatch, WL_LATCH_SET, 0);
- ResetLatch(MyLatch);
- /* check for deadlocks first, as that's probably log-worthy */
- if (got_deadlock_timeout)
+ if (InHotStandby)
+ {
+ /* Set a timer and wait for that or for the Lock to be granted */
+ ResolveRecoveryConflictWithLock(locallock->tag.lock);
+ }
+ else
{
- CheckDeadLock();
- got_deadlock_timeout = false;
+ WaitLatch(MyLatch, WL_LATCH_SET, 0);
+ ResetLatch(MyLatch);
+ /* check for deadlocks first, as that's probably log-worthy */
+ if (got_deadlock_timeout)
+ {
+ CheckDeadLock();
+ got_deadlock_timeout = false;
+ }
+ CHECK_FOR_INTERRUPTS();
}
- CHECK_FOR_INTERRUPTS();
/*
* waitStatus could change from STATUS_WAITING to something else
* already caused QueryCancelPending to become set, we want the cancel to
* be reported as a lock timeout, not a user cancel.
*/
- if (LockTimeout > 0)
+ if (!InHotStandby)
{
- DisableTimeoutParams timeouts[2];
+ if (LockTimeout > 0)
+ {
+ DisableTimeoutParams timeouts[2];
- timeouts[0].id = DEADLOCK_TIMEOUT;
- timeouts[0].keep_indicator = false;
- timeouts[1].id = LOCK_TIMEOUT;
- timeouts[1].keep_indicator = true;
- disable_timeouts(timeouts, 2);
+ timeouts[0].id = DEADLOCK_TIMEOUT;
+ timeouts[0].keep_indicator = false;
+ timeouts[1].id = LOCK_TIMEOUT;
+ timeouts[1].keep_indicator = true;
+ disable_timeouts(timeouts, 2);
+ }
+ else
+ disable_timeout(DEADLOCK_TIMEOUT, false);
}
- else
- disable_timeout(DEADLOCK_TIMEOUT, false);
/*
* Re-acquire the lock table's partition lock. We have to do this to hold
projects / postgresql / commitdiff