From 49bff5300d527f28c7670cdfad9e4a1b8f5ccdea Mon Sep 17 00:00:00 2001 From: Simon Riggs Date: Wed, 22 Mar 2017 16:37:28 +0000 Subject: [PATCH] Assign AccessExclusiveLocks against subxacts in Hot Standby MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Previously AELs were registered against the top-level xid, which could cause locks to be held much longer than necessary in some cases during Hot Standby replay. We now record locks directly against their appropriate xids. Requires few code changes because original code allowed for this situation but didn’t fully implement it. Discussion: CAKJS1f9vJ841HY=wonnLVbfkTWGYWdPN72VMxnArcGCjF3SywA@mail.gmail.com Author: Simon Riggs and David Rowley --- src/backend/storage/ipc/standby.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/src/backend/storage/ipc/standby.c b/src/backend/storage/ipc/standby.c index 7be8fd4a78..8e57f933ca 100644 --- a/src/backend/storage/ipc/standby.c +++ b/src/backend/storage/ipc/standby.c @@ -590,10 +590,6 @@ StandbyLockTimeoutHandler(void) * RelationLockList, so we can keep track of the various entries made by * the Startup process's virtual xid in the shared lock table. * - * We record the lock against the top-level xid, rather than individual - * subtransaction xids. This means AccessExclusiveLocks held by aborted - * subtransactions are not released as early as possible on standbys. - * * List elements use type xl_rel_lock, since the WAL record type exactly * matches the information that we need to keep track of. * @@ -1052,7 +1048,7 @@ LogAccessExclusiveLock(Oid dbOid, Oid relOid) { xl_standby_lock xlrec; - xlrec.xid = GetTopTransactionId(); + xlrec.xid = GetCurrentTransactionId(); /* * Decode the locktag back to the original values, to avoid sending lots @@ -1084,7 +1080,7 @@ LogAccessExclusiveLockPrepare(void) * GetRunningTransactionLocks() might see a lock associated with an * InvalidTransactionId which we later assert cannot happen. */ - (void) GetTopTransactionId(); + (void) GetCurrentTransactionId(); } /*