Re: walsummarizer can get stuck when switching timelines

On Tue, Jul 14, 2026 at 2:09 AM Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>
> Here is a patch, with a test case.
>

I tried the patch on Windows and got following failure:

# executing test in
C:\....\postgresql\build/testrun/pg_walsummary/003_tli_switch group
pg_walsummary test 003_tli_switch
# initializing database system by copying initdb template
not ok 1 - WAL summarization on node3 advanced past timeline switch
ok 2 - no summaries from before LSN 0/04016090
not ok 3 - at least one summary from LSN 0/04016090 or later
1..3
# test failed
----------------------------------- stderr -----------------------------------
# poll_query_until timed out executing this query:
# SELECT EXISTS (SELECT * FROM pg_available_wal_summaries() WHERE tli = 2)
#
# expecting this output:
# t
# last actual query output:
# f
# with stderr:
# Failed test 'WAL summarization on node3 advanced past timeline switch'
# at C:/Workspace/code/postgresql/src/bin/pg_walsummary/t/003_tli_switch.pl
line 92.
# Failed test 'at least one summary from LSN 0/04016090 or later'
# at C:/Workspace/code/postgresql/src/bin/pg_walsummary/t/003_tli_switch.pl
line 109.
# Looks like you failed 2 tests of 3.

(test program exited with status code 2)
==============================================================================

The failure log of node-3 is attached. I'll investigate this further
and share my findings but in the meantime if you have any inputs based
on the LOG then do let me know.

--
With Regards,
Amit Kapila.