From: Fujii Masao <fujii@postgresql.org>
Date: Wed, 28 Jul 2021 16:35:52 +0000 (+0900)
Subject: Update minimum recovery point on truncation during WAL replay of abort record.
X-Git-Tag: REL9_6_23~18
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=32d182dd0da9628a4bc1515b69694d6e361a8de4;p=thirdparty%2Fpostgresql.git

Update minimum recovery point on truncation during WAL replay of abort record.

If a file is truncated, we must update minRecoveryPoint. Once a file is
truncated, there's no going back; it would not be safe to stop recovery
at a point earlier than that anymore.

Commit 7bffc9b7bf changed xact_redo_commit() so that it updates
minRecoveryPoint on truncation, but forgot to change xact_redo_abort().

Back-patch to all supported versions.

Reported-by: mengjuan.cmj@alibaba-inc.com
Author: Fujii Masao
Reviewed-by: Heikki Linnakangas
Discussion: https://postgr.es/m/b029fce3-4fac-4265-968e-16f36ff4d075.mengjuan.cmj@alibaba-inc.com
---

diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index e75062e0f96..2ccb582100e 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -5545,7 +5545,8 @@ xact_redo_commit(xl_xact_parsed_commit *parsed,
  * because subtransaction commit is never WAL logged.
  */
 static void
-xact_redo_abort(xl_xact_parsed_abort *parsed, TransactionId xid)
+xact_redo_abort(xl_xact_parsed_abort *parsed, TransactionId xid,
+				XLogRecPtr lsn)
 {
 	TransactionId max_xid;
 
@@ -5607,7 +5608,16 @@ xact_redo_abort(xl_xact_parsed_abort *parsed, TransactionId xid)
 	}
 
 	/* Make sure files supposed to be dropped are dropped */
-	DropRelationFiles(parsed->xnodes, parsed->nrels, true);
+	if (parsed->nrels > 0)
+	{
+		/*
+		 * See comments about update of minimum recovery point on truncation,
+		 * in xact_redo_commit().
+		 */
+		XLogFlush(lsn);
+
+		DropRelationFiles(parsed->xnodes, parsed->nrels, true);
+	}
 }
 
 void
@@ -5651,12 +5661,12 @@ xact_redo(XLogReaderState *record)
 		if (info == XLOG_XACT_ABORT)
 		{
 			Assert(!TransactionIdIsValid(parsed.twophase_xid));
-			xact_redo_abort(&parsed, XLogRecGetXid(record));
+			xact_redo_abort(&parsed, XLogRecGetXid(record), record->EndRecPtr);
 		}
 		else
 		{
 			Assert(TransactionIdIsValid(parsed.twophase_xid));
-			xact_redo_abort(&parsed, parsed.twophase_xid);
+			xact_redo_abort(&parsed, parsed.twophase_xid, record->EndRecPtr);
 			RemoveTwoPhaseFile(parsed.twophase_xid, false);
 		}
 	}