From e43f947bf32f3ea4caa5b895ca7c7659b17192ae Mon Sep 17 00:00:00 2001 From: Heikki Linnakangas Date: Wed, 19 Dec 2012 14:13:23 +0200 Subject: [PATCH] Check if we've reached end-of-backup point also if no redo is required. If you restored from a backup taken from a standby, and the last record in the backup is the checkpoint record, ie. there is no redo required except for the checkpoint record, we would fail to notice that we've reached the end-of-backup point, and the database is consistent. The result was an error "WAL ends before end of online backup". To fix, move the have-we-reached-end-of-backup check into CheckRecoveryConsistency(), which is already responsible for similar checks with minRecoveryPoint, and is called in the right places. Backpatch to 9.2, this check and bug did not exist before that. --- src/backend/access/transam/xlog.c | 49 ++++++++++++++++++------------- 1 file changed, 28 insertions(+), 21 deletions(-) diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c index 2deb7e5d89..5b156f9c70 100644 --- a/src/backend/access/transam/xlog.c +++ b/src/backend/access/transam/xlog.c @@ -5963,27 +5963,6 @@ StartupXLOG(void) /* Pop the error context stack */ error_context_stack = errcallback.previous; - if (!XLogRecPtrIsInvalid(ControlFile->backupEndPoint) && - XLByteLE(ControlFile->backupEndPoint, EndRecPtr)) - { - /* - * We have reached the end of base backup, the point where - * the minimum recovery point in pg_control indicates. The - * data on disk is now consistent. Reset backupStartPoint - * and backupEndPoint. - */ - elog(DEBUG1, "end of backup reached"); - - LWLockAcquire(ControlFileLock, LW_EXCLUSIVE); - - MemSet(&ControlFile->backupStartPoint, 0, sizeof(XLogRecPtr)); - MemSet(&ControlFile->backupEndPoint, 0, sizeof(XLogRecPtr)); - ControlFile->backupEndRequired = false; - UpdateControlFile(); - - LWLockRelease(ControlFileLock); - } - /* * Update lastReplayedEndRecPtr after this record has been * successfully replayed. @@ -6390,6 +6369,34 @@ CheckRecoveryConsistency(void) if (XLogRecPtrIsInvalid(minRecoveryPoint)) return; + /* + * Have we reached the point where our base backup was completed? + */ + if (!XLogRecPtrIsInvalid(ControlFile->backupEndPoint) && + XLByteLE(ControlFile->backupEndPoint, EndRecPtr)) + { + /* + * We have reached the end of base backup, as indicated by pg_control. + * The data on disk is now consistent. Reset backupStartPoint and + * backupEndPoint, and update minRecoveryPoint to make sure we don't + * allow starting up at an earlier point even if recovery is stopped + * and restarted soon after this. + */ + elog(DEBUG1, "end of backup reached"); + + LWLockAcquire(ControlFileLock, LW_EXCLUSIVE); + + if (XLByteLT(ControlFile->minRecoveryPoint, EndRecPtr)) + ControlFile->minRecoveryPoint = EndRecPtr; + + MemSet(&ControlFile->backupStartPoint, 0, sizeof(XLogRecPtr)); + MemSet(&ControlFile->backupEndPoint, 0, sizeof(XLogRecPtr)); + ControlFile->backupEndRequired = false; + UpdateControlFile(); + + LWLockRelease(ControlFileLock); + } + /* * Have we passed our safe starting point? Note that minRecoveryPoint * is known to be incorrectly set if ControlFile->backupEndRequired, -- 2.40.0