Date: Wed, 20 Aug 2025 18:08:11 +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 Wed, Aug 20, 2025 at 08:14:47AM -0700, Adrian Klaver wrote:
> Hmm.
> 
> From initial post:
> 
> "For ~ 1 second there are no logs going to log (we usually have at 5-20
> messages logged per second), no connection, nothing. And then we get
> bunch (30+) messages with the same milisecond time."
> 
> Are the 30+ messages all coming in on one connection or multiple
> connections?

Multiple connections.

> Also to be clear these are statements that are being run on the replica
> locally, correct?

What do you mean locally?

Application servers are *not* on the same server as the db. So no, they
are not local.

> Does the AWS monitoring indicate any issues?

Nope. All looks "fine".

Same for our monitoring  - CPU usage, iops, load.

Best regards,

depesz