Message-ID: <82d9b8f97e58718be841129026fabfd85ddb7ba2.camel@cybertec.at>
Subject: Re: terminating connection due to conflict with recovery
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Don Seiler <don@seiler.us>, Pgsql-admin
 <pgsql-admin@lists.postgresql.org>
Date: Fri, 09 Oct 2020 17:06:00 +0200
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 <CAHJZqBBgGZdF2GuE5a6KUW4daxgNgOAwP2N=x+ZYFmzXpAJ3VQ@mail.gmail.com>
References: 
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On Thu, 2020-10-08 at 10:17 -0500, Don Seiler wrote:
> I have a PG 12.4 read replica that we're using to offload short read-only queries from the primary. However this morning (and random other days/times, it seems), I see batches of these messages in
> the replica PG log:
> 
> FATAL:  terminating connection due to conflict with recovery
> 
> I have hot_standby_feedback enabled already, but looking further at this message, it isn't cancelling the transaction but rather terminating the connection entirely. This suggests perhaps that a
> session is sitting "idle in transaction" for 30 seconds (our max_standby_streaming_delay is at the default 30s)? Or that a group of sessions are "idle in transaction" and overlapping enough that
> recovery is blocked for 30 seconds?

What do you find in "pg_stat_database_conflicts"?

Yours,
Laurenz Albe
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