From: Bernd Helmle <mailings@oopsware.de>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Kevin Grittner <Kevin.Grittner@wicourts.gov>
Cc: Andrew Dunstan <andrew@dunslane.net>
Cc: pgsql-hackers@postgresql.org
Subject: Re: no universally correct setting for fsync
Date: Sat, 08 May 2010 02:16:23 +0200
Message-ID: <D9EB8B28CCC10C46B7DD3472@amenophis> (raw)
In-Reply-To: <3860.1273276155@sss.pgh.pa.us>
References: <4BE3D3930200002500031382@gw.wicourts.gov>
<4BE425F7.30804@dunslane.net>
<4BE3E205020000250003138F@gw.wicourts.gov>
<A1EBC6E5100210B51612365E@amenophis>
<3860.1273276155@sss.pgh.pa.us>
--On 7. Mai 2010 19:49:15 -0400 Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Bernd Helmle <mailings@oopsware.de> writes:
>> I've recently even started to wonder if the performance gain with
>> fsync=off is still that large on modern hardware. While testing large
>> migration procedures to a new version some time ago (on an admitedly
>> fast storage) i forgot here and then to turn it off, without a
>> significant degradation in performance.
>
> That says to me either that you're using a battery-backed write cache,
> or your fsyncs don't really work (no write barriers or something like
> that).
>
Well, yes, BBU present and proven storage. Maybe i'm wrong, but it seems
battery backed write caches aren't that seldom even in low end systems
nowadays.
--
Thanks
Bernd
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-docs@postgresql.org
Cc: mailings@oopsware.de, tgl@sss.pgh.pa.us, Kevin.Grittner@wicourts.gov, andrew@dunslane.net, pgsql-hackers@postgresql.org
Subject: Re: no universally correct setting for fsync
In-Reply-To: <D9EB8B28CCC10C46B7DD3472@amenophis>
* 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