Received: from localhost (unknown [200.46.204.183]) by postgresql.org (Postfix) with ESMTP id 02E26650247 for ; Tue, 12 Aug 2008 21:52:51 -0300 (ADT) Received: from postgresql.org ([200.46.204.86]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 71771-02-8 for ; Tue, 12 Aug 2008 21:52:20 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from smtp107.biz.mail.mud.yahoo.com (smtp107.biz.mail.mud.yahoo.com [68.142.200.255]) by postgresql.org (Postfix) with SMTP id 5E14B650394 for ; Tue, 12 Aug 2008 21:40:20 -0300 (ADT) Received: (qmail 40042 invoked from network); 13 Aug 2008 00:40:18 -0000 Received: from unknown (HELO ?192.168.5.112?) (ramayer@forensiclogic.com@75.37.20.87 with plain) by smtp107.biz.mail.mud.yahoo.com with SMTP; 13 Aug 2008 00:40:17 -0000 X-YMail-OSG: onC6u0YVM1lVpwuWAHyZ1_dwApcdfHoXN5WVqNluZsX.lEdxMqU_dYBhqQGPKuPI._zmIi6bAsBtY779kQ4EKT8NTCiqn6Sx6KNjICDSK.Jbdmxky9NX7X19RLM8E6L0z6c- X-Yahoo-Newman-Property: ymail-3 Message-ID: <48A22D72.6030306@cheapcomplexdevices.com> Date: Tue, 12 Aug 2008 17:40:18 -0700 From: Ron Mayer User-Agent: Thunderbird 2.0.0.16 (X11/20080724) MIME-Version: 1.0 To: Scott Carey CC: Ron Mayer , Greg Smith , Henrik , pgsql-performance@postgresql.org Subject: Re: Filesystem benchmarking for pg 8.3.3 server References: <32A7A76B-16CA-4CDB-AD43-973AD6A3FC7B@mac.se> <48A2050D.4050803@cheapcomplexdevices.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=0 tagged_above=0 required=5 tests=none X-Spam-Level: X-Archive-Number: 200808/140 X-Sequence-Number: 31021 Scott Carey wrote: > Some SATA drives were known to not flush their cache when told to. Can you name one? The ATA commands seem pretty clear on the matter, and ISTM most of the reports of these issues came from before Linux had write-barrier support. I've yet to hear of a drive with the problem; though no doubt there are some cheap RAID controllers somewhere that expect you to disable the drive caches.