Message-ID: <2a301859ab47c2e83ba5c8ebf75112d61246a8cd.camel@cybertec.at>
Subject: Re: wal segment size
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Colin 't Hart <colinthart@gmail.com>, PostgreSQL General
	 <pgsql-general@lists.postgresql.org>
Date: Wed, 17 Dec 2025 16:25:17 +0100
In-Reply-To: <CAMon-aQ8X7H7jCC6ggKm9Uzcu3KfGVC34RRqKt8BCfpDn2tq9A@mail.gmail.com>
References: 
	<CAMon-aQ8X7H7jCC6ggKm9Uzcu3KfGVC34RRqKt8BCfpDn2tq9A@mail.gmail.com>
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On Wed, 2025-12-17 at 16:13 +0100, Colin 't Hart wrote:
> I see very little advice on tuning WAL=C2=A0segment=C2=A0size.
>=20
> One of my clients has a few datawarehouses=C2=A0at around 8 - 16 TB
>=20
> On one of the nodes there are approx 15000 WAL segments of 16MB each, tot=
alling
> approx 230GB. The archiver is archiving approx one per second, so approx =
4 hours to clear.
>=20
> Would=C2=A0we gain anything by bumping the WAL=C2=A0segment size?

Very likely yes, if the problem is the overhead of starting the archive_com=
mand.

Another thing that can slow down archiving is if you compress these segment=
s
too aggressively.

Yours,
Laurenz Albe