Date: Fri, 19 Jun 2026 12:07:21 +0200
From: hubert depesz lubaczewski <depesz@depesz.com>
Sender: depesz@depesz.com
To: Laurenz Albe <laurenz.albe@cybertec.at>
Cc: Thom Brown <thom@linux.com>,
	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 Fri, Jun 19, 2026 at 09:06:12AM +0200, Laurenz Albe wrote:
> 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?
> > 
> > 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!
> 
> Could it be bug #19490 [1]?
> That would be fixed in the next minor releases.

Maybe it's related, but there are two issues:
1. it's not streaming replication
2. waitevent/type doesn't match. in my case it's
   IPC/RecoveryConflictSnapshot

Best regards,

depesz