Message-ID: <ee2fe0e07f8d4e9af696a9f7e254f46b6bf3b347.camel@cybertec.at>
Subject: Re: Why is WAL-file based replica stuck for long time (hour?) in
 IPC:RecoveryConflictSnapshot ?
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: depesz@depesz.com, Thom Brown <thom@linux.com>
Cc: pgsql-general mailing list <pgsql-general@postgresql.org>
Date: Fri, 19 Jun 2026 09:06:12 +0200
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References: <ajPdELE6JOtO7bk8@depesz.com>
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On Thu, 2026-06-18 at 15:33 +0200, hubert depesz lubaczewski wrote:
> On Thu, Jun 18, 2026 at 02:07:36PM +0100, Thom Brown wrote:
> > Have you got anything in the logs that say "conflict with recovery"?
> > Also, I know you are just running count(*), but is there a transaction
> > being left open?
> > SELECT pid, state, xact_start, query
> > FROM pg_stat_activity
> > ORDER BY xact_start NULLS LAST;
> > Any 'idle in transaction' for too long?
> > What is max_standby_streaming_delay and hot_standby_feedback set to?
>=20
> No transactions were happening then. These are our "Disaster Recovery"
> instances, and they are generally unused.
>=20
> max_standby_streaming_delay is 10 minutes
> hot_standby_feedback is on.
>=20
> Please note that these are *NOT* doing streaming replication!

Could it be bug #19490 [1]?
That would be fixed in the next minor releases.

Yours,
Laurenz Albe

 [1]: https://postgr.es/m/flat/19490-9c59c6a583513b99%40postgresql.org