Re: Race conditions in 019_replslot_limit.pl

Hi,

I think I did find a bug related to the test, but afaics not the cause of the
test failures we're seeing. See
https://www.postgresql.org/message-id/20220223014855.4lsddr464i7mymk2%40alap3.anarazel.de

I don't think it's related to the problem of this thread, because the logs of
primary3 don't have a single mention of

ereport(LOG,
(errmsg("terminating process %d to release replication slot \"%s\"",
active_pid, NameStr(slotname))));

On 2022-02-18 15:14:15 -0800, Andres Freund wrote:
> I'm running out of ideas for how to try to reproduce this. I think we might
> need some additional debugging information to get more information from the
> buildfarm.

> I'm thinking of adding log_min_messages=DEBUG2 to primary3, passing --verbose
> to pg_basebackup in $node_primary3->backup(...).
>
> It might also be worth adding DEBUG2 messages to ReplicationSlotShmemExit(),
> ReplicationSlotCleanup(), InvalidateObsoleteReplicationSlots().

Planning to commit something like the attached.

Greetings,

Andres Freund