upstream/postgresql
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2026-04-04 16:55:45 -04:00
Code Issues Projects Releases Packages Wiki Activity Actions

Fix WAL flush LSN used by logical walsender during shutdown

Browse source 
Commit 6eedb2a5fd made the logical walsender call
XLogFlush(GetXLogInsertRecPtr()) to ensure that all pending WAL is flushed,
fixing a publisher shutdown hang. However, if the last WAL record ends at
a page boundary, GetXLogInsertRecPtr() can return an LSN pointing past
the page header, which can cause XLogFlush() to report an error.

A similar issue previously existed in the GiST code. Commit b1f14c9672
introduced GetXLogInsertEndRecPtr(), which returns a safe WAL insertion end
location (returning the start of the page when the last record ends at a page
boundary), and updated the GiST code to use it with XLogFlush().

This commit fixes the issue by making the logical walsender use
XLogFlush(GetXLogInsertEndRecPtr()) when flushing pending WAL during shutdown.

Backpatch to all supported versions.

Reported-by: Andres Freund <andres@anarazel.de>
Author: Anthonin Bonnefoy <anthonin.bonnefoy@datadoghq.com>
Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/vzguaguldbcyfbyuq76qj7hx5qdr5kmh67gqkncyb2yhsygrdt@dfhcpteqifux
Backpatch-through: 14
This commit is contained in:
Fujii Masao 2026-03-17 08:10:20 +09:00
parent 2fa42feb79
commit 8ee536c895
1 changed files with 7 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

8
src/backend/replication/walsender.c
View file

@ -1881,9 +1881,15 @@ WalSndWaitForWal(XLogRecPtr loc)
* If we're shutting down, trigger pending WAL to be written out,
* otherwise we'd possibly end up waiting for WAL that never gets
* written, because walwriter has shut down already.
*
* Note that GetXLogInsertEndRecPtr() is used to obtain the WAL flush
* request location instead of GetXLogInsertRecPtr(). Because if the
* last WAL record ends at a page boundary, GetXLogInsertRecPtr() can
* return an LSN pointing past the page header, which may cause
* XLogFlush() to report an error.
*/
if (got_STOPPING && !RecoveryInProgress())
XLogFlush(GetXLogInsertRecPtr());
XLogFlush(GetXLogInsertEndRecPtr());
/*
* To avoid the scenario where standbys need to catch up to a newer