Hi,
I noticed that this sequence of actions (for temporary table) leads to
an error, if
temp_table_max_size parameter is set :
***
LockRelationForExtension(relation, ExclusiveLock);
buf = ReadBuffer(relation, P_NEW);
***
Error occurs during total temporary table size calculation
(find_total_temp_relation_size function,
that can be called only if temp_table_max_size parameter > 0) : we are
trying to open all table's
indexes and append their size to the total size of the temporary
table. But inside relation_open function
(called for index) we meet this assert (and, of course, fail on it):
***
/*
* We don't acquire any other heavyweight lock while holding the relation
* extension lock. We do allow to acquire the same relation extension
* lock more than once but that case won't reach here.
*/
Assert(!IsRelationExtensionLockHeld);
***
I suppose that the simplest way out of the situation would be to skip
locking temporary tables for
extension
--
Best regards,
Daniil Davydov
From da84d916e568be0d2414303f4a1e1d01b0bc6abd Mon Sep 17 00:00:00 2001
From: Daniil Davidov <davydovdaniil...@gmail.com>
Date: Fri, 6 Dec 2024 16:41:53 +0700
Subject: [PATCH] Fix bug with locking temp relation for extension
---
src/backend/storage/lmgr/lmgr.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/src/backend/storage/lmgr/lmgr.c b/src/backend/storage/lmgr/lmgr.c
index 094522acb4..0a91109d03 100644
--- a/src/backend/storage/lmgr/lmgr.c
+++ b/src/backend/storage/lmgr/lmgr.c
@@ -421,6 +421,9 @@ LockRelationForExtension(Relation relation, LOCKMODE lockmode)
{
LOCKTAG tag;
+ if (relation->rd_islocaltemp)
+ return;
+
SET_LOCKTAG_RELATION_EXTEND(tag,
relation->rd_lockInfo.lockRelId.dbId,
relation->rd_lockInfo.lockRelId.relId);
--
2.43.0
