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Correct logical decoding status at end of recovery with minimal WAL level.

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Crash recovery running with wal_level='minimal' can replay an
XLOG_LOGICAL_DECODING_STATUS_CHANGE record that activates logical
decoding, if the server previously ran with a higher wal_level and
crashed after the last logical slot was dropped but before the
checkpointer deactivated logical decoding. Replaying such a record is
correct since it reflects the status at the time it was
written. However, UpdateLogicalDecodingStatusEndOfRecovery() asserted
that logical decoding is never active with wal_level='minimal',
causing an assertion failure at the end of recovery. In production
builds, logical decoding would remain active while running with
wal_level='minimal'.

Instead of special-casing wal_level='minimal', recompute the status at
the end of recovery as usual: no logical slot can exist with
wal_level='minimal' as RestoreSlotFromDisk() would have rejected it,
so the recomputation always deactivates logical decoding in this case,
also writing the corresponding status change record.

Oversight in 67c20979ce.

Reviewed-by: Guoqing Yang <yanggq1988@126.com>
Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Discussion: https://postgr.es/m/CAD21AoAnPAugUnDic+ESvrfXjXHk2bss9eHAD7zP0-Chy2UabA@mail.gmail.com
Backpatch-through: 19
This commit is contained in:
Masahiko Sawada
2026-07-16 12:13:16 -07:00
parent 2a933deaa2
commit baf0ec4652
1 changed files with 9 additions and 11 deletions
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20
src/backend/replication/logical/logicalctl.c
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@@ -561,19 +561,17 @@ UpdateLogicalDecodingStatusEndOfRecovery(void)
Assert(RecoveryInProgress());
/*
* With 'minimal' WAL level, there are no logical replication slots during
* recovery. Logical decoding is always disabled, so there is no need to
* synchronize XLogLogicalInfo.
*/
if (wal_level == WAL_LEVEL_MINIMAL)
{
Assert(!IsXLogLogicalInfoEnabled() && !IsLogicalDecodingEnabled());
return;
}
LWLockAcquire(LogicalDecodingControlLock, LW_EXCLUSIVE);
/*
* With 'minimal' WAL level, no logical replication slot can exist (see
* RestoreSlotFromDisk()), so the new status is always false. However,
* logical decoding could have been enabled during recovery by replaying
* an XLOG_LOGICAL_DECODING_STATUS_CHANGE record from WAL generated with a
* higher wal_level, e.g. if the server crashed right after the last
* logical slot was dropped and then restarted with wal_level='minimal'.
* The code below disables logical decoding in that case.
*/
if (wal_level == WAL_LEVEL_LOGICAL || CheckLogicalSlotExists())
new_status = true;