Received: from maia.hub.org (unknown [200.46.204.183]) by mail.postgresql.org (Postfix) with ESMTP id 12C6D632DCD for ; Mon, 11 Jan 2010 16:26:13 -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 42052-06 for ; Mon, 11 Jan 2010 20:26:02 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from sss.pgh.pa.us (sss.pgh.pa.us [66.207.139.130]) by mail.postgresql.org (Postfix) with ESMTP id 87558633407 for ; Mon, 11 Jan 2010 16:26:02 -0400 (AST) Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1]) by sss.pgh.pa.us (8.14.2/8.14.2) with ESMTP id o0BKPvZR018928; Mon, 11 Jan 2010 15:25:58 -0500 (EST) To: Scott Marlowe cc: "Dusek, Bob" , Bob Dusek , Kevin Grittner , "pgsql-performance@postgresql.org" Subject: Re: performance config help In-reply-to: References: <6EB5F166D3FA6B499A1A25856BDB9B6085F4A309@susday216.corp.ncr.com> Comments: In-reply-to Scott Marlowe message dated "Mon, 11 Jan 2010 13:16:45 -0700" Date: Mon, 11 Jan 2010 15:25:57 -0500 Message-ID: <18927.1263241557@sss.pgh.pa.us> From: Tom Lane X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=2.078 tagged_above=-10 required=5 tests=BAYES_05=-1.11, FH_DATE_PAST_20XX=3.188 X-Spam-Level: ** X-Archive-Number: 201001/217 X-Sequence-Number: 37097 Scott Marlowe writes: > On Mon, Jan 11, 2010 at 1:13 PM, Dusek, Bob wrote: >> I haven't been involved in any benchmarking of PG8 with fsync=off, but we certainly did it with PG 7.4.  fsync=0ff, for our purposes, was MUCH faster. > And many changes have been made since then to make fsyncing much > faster. You may be grinding the valves on a 2009 Ferrari because > pappy used to have to do it on his 1958 pickup truck here. Perhaps more to the point, synchronous_commit can get most of the same speedup with much less risk to your database. You really owe it to yourself to redo that benchmarking with a recent PG release. regards, tom lane