X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id 1EC8852A8A for ; Sat, 16 Jul 2005 08:01:16 -0300 (ADT) Received: from svr1.postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 33148-06 for ; Sat, 16 Jul 2005 11:01:11 +0000 (GMT) Received: from vms040pub.verizon.net (vms040pub.verizon.net [206.46.252.40]) by svr1.postgresql.org (Postfix) with ESMTP id 3E4E952A81 for ; Sat, 16 Jul 2005 08:01:07 -0300 (ADT) Received: from osgiliath.mathom.us ([70.108.53.154]) by vms040.mailsrvcs.net (Sun Java System Messaging Server 6.2 HotFix 0.04 (built Dec 24 2004)) with ESMTPA id <0IJP0087AVXXZG04@vms040.mailsrvcs.net> for pgsql-performance@postgresql.org; Sat, 16 Jul 2005 06:01:09 -0500 (CDT) Received: from localhost (localhost [127.0.0.1]) by osgiliath.mathom.us (Postfix) with ESMTP id 1EB796005E6; Sat, 16 Jul 2005 07:01:09 -0400 (EDT) Received: from osgiliath.mathom.us ([127.0.0.1]) by localhost (osgiliath [127.0.0.1]) (amavisd-new, port 10024) with LMTP id 23919-01-8; Sat, 16 Jul 2005 07:01:09 -0400 (EDT) Received: by osgiliath.mathom.us (Postfix, from userid 1000) id F313B600197; Sat, 16 Jul 2005 07:01:08 -0400 (EDT) Date: Sat, 16 Jul 2005 07:01:08 -0400 From: Michael Stone Subject: Re: more filesystem benchmarks In-reply-to: <1121501547.7101.18.camel@noodles> To: "Jeffrey W. Baker" Cc: pgsql-performance@postgresql.org Mail-Followup-To: "Jeffrey W. Baker" , pgsql-performance@postgresql.org Message-id: <20050716110108.GL19080@mathom.us> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii; format=flowed Content-disposition: inline X-Pgp-Fingerprint: 53 FF 38 00 E7 DD 0A 9C 84 52 84 C5 EE DF 7C 88 X-Virus-Scanned: by amavisd-new-20030616-p10 (Debian) at mathom.us References: <1121501547.7101.18.camel@noodles> User-Agent: Mutt/1.5.9i X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.009 tagged_above=0 required=5 tests=AWL X-Spam-Level: X-Archive-Number: 200507/234 X-Sequence-Number: 13475 On Sat, Jul 16, 2005 at 01:12:27AM -0700, Jeffrey W. Baker wrote: >Another frequent suggestion is to put the xlog on a separate device. I >tried this, and, for a given number of disks, it appears to be >counter-productive. A RAID5 of 5 disks holding both logs and data is >about 15% faster than a RAID5 of 3 disks with the data, and a mirror of >two disks holding the xlog. Try simply a seperate partition on the same device with a different filesystem (ext2). Mike Stone