Date: Thu, 21 Aug 2025 18:51:45 +0200
From: hubert depesz lubaczewski <depesz@depesz.com>
Sender: depesz@depesz.com
To: Adrian Klaver <adrian.klaver@aklaver.com>
Cc: PostgreSQL General <pgsql-general@lists.postgresql.org>
Subject: Re: Streaming replica hangs periodically for ~ 1 second - how to
 diagnose/debug
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On Thu, Aug 21, 2025 at 08:59:03AM -0700, Adrian Klaver wrote:
> Getting to the bottom of the bag of ideas:
> Have you looked at the OS system log for the time period involved?

Yes. Mostly dmesg. Nothing interesting logged around the time.

> You mentioned this seemed to involve PREPARE and DISCARD ALL.
> Is this the same set of statements or is it all over the place?

No. From what I can tell it's random sample.

> Also it would be helpful to know what bouncer you are actually using and
> what mode you are running in?

pgBouncer, version 1.23.1. As for more... mostly transaction pooling.
Applications go using transaction pooling, but people (dbas, ops) have
session pooling.

Best regards,

depesz