From: Tom Lane <tgl@sss.pgh.pa.us>
To: Alvaro Herrera <alvherre@commandprompt.com>
Cc: Josh Berkus <josh@agliodbs.com>
Cc: Heikki Linnakangas <heikki@enterprisedb.com>
Cc: pgsql-hackers@postgresql.org, Robert Treat <xzilla@users.sourceforge.net>
Cc: Peter Eisentraut <peter_e@gmx.net>
Cc: Greg Smith <gsmith@gregsmith.com>
Cc: Andreas Pflug <pgadmin@pse-consulting.de>
Cc: Decibel! <decibel@decibel.org>
Subject: Re: Overhauling GUCS
Date: Wed, 11 Jun 2008 17:05:15 -0400
Message-ID: <11913.1213218315@sss.pgh.pa.us> (raw)
In-Reply-To: <20080611163847.GN5352@alvh.no-ip.org>
References: <48409D1E.3070208@agliodbs.com>
<200806061624.29105.xzilla@users.sourceforge.net>
<200806100937.38124.josh@agliodbs.com>
<200806100949.17918.josh@agliodbs.com>
<21875.1213122184@sss.pgh.pa.us>
<484F7613.5070202@enterprisedb.com>
<484FFF06.9010307@agliodbs.com>
<20080611163847.GN5352@alvh.no-ip.org>
Alvaro Herrera <alvherre@commandprompt.com> writes:
> Josh Berkus wrote:
>> Ideally, of course, there would be no wal_buffers setting, and WAL
>> buffers would be allocated from shared_buffers pool on demand...
> Same for pg_subtrans, pg_clog, etc (as previously discussed)
I agree with that for pg_clog and friends, but I'm much more leery of
folding WAL into the same framework. Its access pattern is *totally*
unlike standard caches, so the argument that this would be good for
performance is resting on nothing but imagination. Also I'm concerned
about possible deadlocks, because WAL is customarily accessed while
holding one or more exclusive buffer locks.
regards, tom lane
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-hackers@postgresql.org
Cc: tgl@sss.pgh.pa.us, alvherre@commandprompt.com, josh@agliodbs.com, heikki@enterprisedb.com, xzilla@users.sourceforge.net, peter_e@gmx.net, gsmith@gregsmith.com, pgadmin@pse-consulting.de, decibel@decibel.org
Subject: Re: Overhauling GUCS
In-Reply-To: <11913.1213218315@sss.pgh.pa.us>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox