Feedback-ID: ia2694551:Fastmail
Date: Mon, 9 Feb 2026 13:40:51 +0100
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Chao Li <li.evan.chao@gmail.com>
Cc: Euler Taveira <euler@eulerto.com>, japin <japinli@hotmail.com>,
	Andres Freund <andres@anarazel.de>, pgsql-hackers@lists.postgresql.org
Subject: Re: log_min_messages per backend type
Message-ID: <202602091231.ybwsbdbxsbdo@alvherre.pgsql>
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On 2026-Feb-09, Chao Li wrote:

> While it’s reasonable to configure a full comma-separated list in
> postgresql.conf, it seems there’s currently no convenient way for a
> superuser to change the log level of a single process type. For
> example:
> 
> ```
> evantest=# alter system set log_min_messages='backend:debug4';
> ERROR:  invalid value for parameter "log_min_messages": "backend:debug4"
> DETAIL:  Default log level was not defined.
> ```
> 
> This feels a bit inconvenient in practice. Intuitively, it would be
> nice if setting a single type:level could be merged into the existing
> log_min_messages value, rather than requiring users to restate the
> entire configuration.

This has been discussed before and no satisfactory solution has been
found.  You're welcome to spend time thinking on this; see e.g.
https://postgr.es/m/20200928033924.GA998042@toroid.org where not only
the details were discussed, but also some links to other threads about
the same idea were given.

-- 
Álvaro Herrera               48°01'N 7°57'E  —  https://www.EnterpriseDB.com/