Date: Thu, 18 Jun 2026 15:33:56 +0200
From: hubert depesz lubaczewski <depesz@depesz.com>
Sender: depesz@depesz.com
To: Thom Brown <thom@linux.com>
Cc: pgsql-general mailing list <pgsql-general@postgresql.org>
Subject: Re: Why is WAL-file based replica stuck for long time (hour?) in
 IPC:RecoveryConflictSnapshot ?
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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?

No transactions were happening then. These are our "Disaster Recovery"
instances, and they are generally unused.

max_standby_streaming_delay is 10 minutes
hot_standby_feedback is on.

Please note that these are *NOT* doing streaming replication!

Best regards,

depesz