Received: from maia.hub.org (maia-3.hub.org [200.46.204.243]) by mail.postgresql.org (Postfix) with ESMTP id 6C136633267 for ; Fri, 7 May 2010 10:47:27 -0300 (ADT) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.243]) (amavisd-maia, port 10024) with ESMTP id 73538-04 for ; Fri, 7 May 2010 13:47:18 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from gw.wicourts.gov (gwmta.wicourts.gov [165.219.244.99]) by mail.postgresql.org (Postfix) with ESMTP id 8FBFC632F5F for ; Fri, 7 May 2010 10:47:20 -0300 (ADT) Received: from Courts-MTA by gw.wicourts.gov with Novell_GroupWise; Fri, 07 May 2010 08:47:18 -0500 Message-Id: <4BE3D3930200002500031382@gw.wicourts.gov> X-Mailer: Novell GroupWise Internet Agent 8.0.1 Date: Fri, 07 May 2010 08:47:15 -0500 From: "Kevin Grittner" To: Subject: no universally correct setting for fsync Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Content-Disposition: inline X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-4.21 tagged_above=-5 required=5 tests=BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, T_RP_MATCHES_RCVD=-0.01 X-Spam-Level: X-Archive-Number: 201005/359 X-Sequence-Number: 162022 Someone just posted to the -admin list with a database corrupted while running with fsync=off. I was all set to refer him to the documentation explaining why he should stop doing this, but to my surprise the documentation waffles on the issue way past what I think is reasonable. http://www.postgresql.org/docs/8.4/interactive/runtime-config-wal.html#GUC-FSYNC There are dire-sounding statements interspersed with: | using fsync results in a performance penalty | Due to the risks involved, there is no universally correct setting | for fsync. | If you trust your operating system, your hardware, and your | utility company (or your battery backup), you can consider | disabling fsync. Isn't this a little too rosy a picture to paint? -Kevin