Received: from malur.postgresql.org ([217.196.149.56])
	by arkaria.postgresql.org with esmtps  (TLS1.3) tls
 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
	(Exim 4.96)
	(envelope-from <pgsql-hackers-owner+archive@lists.postgresql.org>)
	id 1weCnW-004dcZ-0B
	for pgsql-hackers@arkaria.postgresql.org;
	Mon, 29 Jun 2026 14:17:18 +0000
Received: from localhost ([127.0.0.1] helo=malur.postgresql.org)
	by malur.postgresql.org with esmtp (Exim 4.96)
	(envelope-from <pgsql-hackers-owner+archive@lists.postgresql.org>)
	id 1weCmV-003aF0-2A
	for pgsql-hackers@arkaria.postgresql.org;
	Mon, 29 Jun 2026 14:16:15 +0000
Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29])
	by malur.postgresql.org with esmtps  (TLS1.3) tls
 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
	(Exim 4.96)
	(envelope-from <myon@debian.org>)
	id 1weCmV-003aEr-16
	for pgsql-hackers@lists.postgresql.org;
	Mon, 29 Jun 2026 14:16:15 +0000
Received: from stravinsky.debian.org ([2001:41b8:202:deb::311:108])
	by magus.postgresql.org with esmtps  (TLS1.3) tls
 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
	(Exim 4.98.2)
	(envelope-from <myon@debian.org>)
	id 1weCmS-00000000nXD-382Q
	for pgsql-hackers@postgresql.org;
	Mon, 29 Jun 2026 14:16:15 +0000
DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=debian.org;
	s=smtpauto.stravinsky; h=X-Debian-User:In-Reply-To:Content-Type:MIME-Version:
	References:Message-ID:Subject:Cc:To:From:Date:Reply-To:
	Content-Transfer-Encoding:Content-ID:Content-Description;
	bh=fk7Ik/ehkhlwr/DqzUjh24ZaGxUYH/VbBinF+zZ01tw=; b=WcHUw0t56tQb7BV/qXTomBaril
	F3itKQUomK0dm3NqDIEl24u+mHyzK2iD++TAKUjB8RuCVp1bxGK3YEgPMCXDCAEcvFY2lsxQXaMaq
	qzZmaKgrnU3B6sEQts40cVN478DSmFOG43/ptl5Ul3gUuKTnRn8jtRUkqzb4nVJhcfXOFQlxS3rRn
	BWeRgIVm5fep9AzI832M/wnMNGLJAfik7V9sh5aJaxAgMq+PbwyDveD+E7vU+MFOOdrJLN3ykMBu5
	E4OEHYZ6WUogCxOqQsO+AazxoGCsAyQ0H46frAI2tMwt39pVqnjU/Y/5Qw1CzAXx5D2MVKW8T/IhD
	uFZXeoEw==;
Received: from authenticated-user
	by stravinsky.debian.org with esmtpsa
 (TLS1.3:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256)
	(Exim 4.96)
	(envelope-from <myon@debian.org>)
	id 1weCmM-006Lhq-1D;
	Mon, 29 Jun 2026 14:16:06 +0000
Date: Mon, 29 Jun 2026 16:16:04 +0200
From: Christoph Berg <myon@debian.org>
To: John Naylor <johncnaylorls@gmail.com>
Cc: PostgreSQL-development <pgsql-hackers@postgresql.org>,
	Michael Paquier <michael@paquier.xyz>
Subject: Re: [PATCH] Document wal_compression=on
Message-ID: <akJ-JMX235QusQx6@msg.df7cb.de>
Mail-Followup-To: Christoph Berg <myon@debian.org>,
	John Naylor <johncnaylorls@gmail.com>,
	PostgreSQL-development <pgsql-hackers@postgresql.org>,
	Michael Paquier <michael@paquier.xyz>
References: <akJDHRtXwGLTppsQ@msg.df7cb.de>
 <CANWCAZYpQwgs61EF6NO_5L3V0cMZbwPBr15dE13V7Uu8cJ0DsQ@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: 
 <CANWCAZYpQwgs61EF6NO_5L3V0cMZbwPBr15dE13V7Uu8cJ0DsQ@mail.gmail.com>
X-Debian-User: myon
List-Id: <pgsql-hackers.lists.postgresql.org>
List-Help: <https://lists.postgresql.org/manage/>
List-Subscribe: <https://lists.postgresql.org/manage/>
List-Post: <mailto:pgsql-hackers@lists.postgresql.org>
List-Owner: <mailto:pgsql-hackers-owner@lists.postgresql.org>
List-Archive: <https://www.postgresql.org/list/pgsql-hackers>
Archived-At: 
 <https://www.postgresql.org/message-id/akJ-JMX235QusQx6%40msg.df7cb.de>
Precedence: bulk

Re: John Naylor
> +        The value <literal>on</literal> is a deprecated alias for
> <literal>pglz</literal>.
> 
> "deprecated" implies we may remove it someday. I don't think we'd gain
> from doing that, but we could instead call 'on' a "historical
> spelling" of 'pglz'.

Or perhaps leave the door open for picking a better default in the future?

     The value <literal>on</literal> is currently an alias for <literal>pglz</literal>.

(I would be fine with either of the 3 variants.)

Maybe we should also update the postgresql.conf.sample:

 #wal_compression = off                  # enables compression of full-page writes;
-                                        # off, pglz, lz4, zstd, or on
+                                        # off, pglz (or on), lz4, or zstd

(Or just delete it there.)

Christoph