From: Robert Haas <rhaas@postgresql.org>
Date: Thu, 10 Aug 2017 15:20:57 +0000 (-0400)
Subject: Remove incorrect assertion in clog.c
X-Git-Tag: REL_10_BETA4~77
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=ec99dd5aee8b831760046d43098c2d1cf23157ed;p=postgresql

Remove incorrect assertion in clog.c

We must advance the oldest XID that can be safely looked up in clog
*before* truncating CLOG, and the oldest XID that can't be reused
*after* truncating CLOG.  This assertion, and the accompanying
comment, are confused; remove them.

Reported by Neha Sharma.

Discussion: http://postgr.es/m/CANiYTQumC3T=UMBMd1Hor=5XWZYuCEQBioL3ug0YtNQCMMT5wQ@mail.gmail.com
---

diff --git a/src/backend/access/transam/clog.c b/src/backend/access/transam/clog.c
index c34e7e1945..0a7e2b310f 100644
--- a/src/backend/access/transam/clog.c
+++ b/src/backend/access/transam/clog.c
@@ -678,10 +678,6 @@ TruncateCLOG(TransactionId oldestXact, Oid oldestxid_datoid)
 	 */
 	AdvanceOldestClogXid(oldestXact);
 
-	/* vac_truncate_clog already advanced oldestXid */
-	Assert(TransactionIdPrecedesOrEquals(oldestXact,
-										 ShmemVariableCache->oldestXid));
-
 	/*
 	 * Write XLOG record and flush XLOG to disk. We record the oldest xid
 	 * we're keeping information about here so we can ensure that it's always