Received: from maia.hub.org (unknown [200.46.204.183]) by mail.postgresql.org (Postfix) with ESMTP id 7992F6327A0 for ; Thu, 12 Nov 2009 03:15:39 -0400 (AST) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 08944-02 for ; Thu, 12 Nov 2009 07:15:31 +0000 (UTC) Received: from mx3.hub.org (mx3.hub.org [206.223.169.73]) by mail.postgresql.org (Postfix) with ESMTP id C6F866324B4 for ; Thu, 12 Nov 2009 03:15:30 -0400 (AST) X-Greylist: delayed 00:10:47.094488 by SQLgrey-1.7.6 Received: from EXHUB018-2.exch018.msoutlookonline.net (exhub018-2.exch018.msoutlookonline.net [64.78.17.17]) by mx3.hub.org (Postfix) with ESMTP id 9BE1237B5F0 for ; Thu, 12 Nov 2009 02:49:07 -0400 (AST) Received: from EXVMBX018-1.exch018.msoutlookonline.net ([64.78.17.47]) by EXHUB018-2.exch018.msoutlookonline.net ([64.78.17.17]) with mapi; Wed, 11 Nov 2009 22:37:33 -0800 From: Scott Carey To: Greg Smith , Craig James CC: "pgsql-performance@postgresql.org" Date: Wed, 11 Nov 2009 22:37:02 -0800 Subject: Re: limiting performance impact of wal archiving. Thread-Topic: [PERFORM] limiting performance impact of wal archiving. Thread-Index: AcpiKvXBkwNV+NJpTg23D9QwxixotwBN5ULz Message-ID: In-Reply-To: <4AF9A22B.3090506@2ndquadrant.com> Accept-Language: en-US Content-Language: en X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-1.11 tagged_above=-10 required=5 tests=BAYES_05=-1.11 X-Spam-Level: X-Archive-Number: 200911/120 X-Sequence-Number: 36288 > Using ext2 means that you're still exposed to fsck errors on boot after > a crash, which doesn't lose anything but you have to go out of your way > to verify you're not going to get stuck with your server down in that > case. The state of things on the performance side is nicely benchmarked > at > http://www.commandprompt.com/blogs/joshua_drake/2008/04/is_that_performan= ce_i_ > smell_ext2_vs_ext3_on_50_spindles_testing_for_postgresql/ > fsck on a filesystem with 1 folder and files is very very fast. Even if using WAL archiving, there won't be many files/directories to check. Fsck is not an issue if the partition is exclusively for WAL. You can even mount it direct, and avoid having the OS cache those pages if you are using a caching raid controller.