Date: Thu, 29 Jul 2021 17:19:24 -0400
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Cc: tgl@sss.pgh.pa.us, jeff.janes@gmail.com, mk@071.ovh,
	pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #17103: WAL segments are not removed after exceeding
 max_slot_wal_keep_size
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On 2021-Jul-29, Kyotaro Horiguchi wrote:

> At Thu, 29 Jul 2021 16:20:38 +0900 (JST), Kyotaro Horiguchi <horikyota.ntt@gmail.com> wrote in 
> > So it seems to me we need to explicitly prevent unexpected checkpoints
> > from happening maybe by enlarging max_wal_size temporily.
> 
> I ended up with the attached. It causes a checkpoint reliably exactly
> at the aimed timing without.

Thanks for looking into it.  The explanation makes sense, so I pushed
your patch and also fixed one outdated comment I noticed while reading
the related code.  I hope this commit will solve the problem ... it is
quite low probability, so we'll have to wait at least two weeks to make
any conclusion.

-- 
Álvaro Herrera         PostgreSQL Developer  —  https://www.EnterpriseDB.com/