X-Original-To: pgsql-performance-postgresql.org@postgresql.org Received: from localhost (wm.hub.org [200.46.204.128]) by postgresql.org (Postfix) with ESMTP id 880A29FB1BA for ; Mon, 7 Aug 2006 13:55:54 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.128]) (amavisd-new, port 10024) with ESMTP id 28250-06 for ; Mon, 7 Aug 2006 16:55:51 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey- Received: from lists.commandprompt.com (host-130.commandprompt.net [207.173.203.130]) by postgresql.org (Postfix) with ESMTP id A7A2C9FA69A for ; Mon, 7 Aug 2006 13:55:51 -0300 (ADT) Received: from alvh.no-ip.org (201-221-202-139.bk11-dsl.surnet.cl [201.221.202.139]) (authenticated bits=0) by lists.commandprompt.com (8.13.7/8.13.6) with ESMTP id k77GtZ4l017799; Mon, 7 Aug 2006 09:55:36 -0700 Received: by alvh.no-ip.org (Postfix, from userid 1000) id D7EF9C45036; Mon, 7 Aug 2006 12:55:16 -0400 (CLT) Date: Mon, 7 Aug 2006 12:55:16 -0400 From: Alvaro Herrera To: "Jim C. Nasby" Cc: "J. Andrew Rogers" , Milen Kulev , "Pgsql-Performance ((E-mail))" Subject: Re: XFS filessystem for Datawarehousing Message-ID: <20060807165516.GA26021@alvh.no-ip.org> Mail-Followup-To: "Jim C. Nasby" , "J. Andrew Rogers" , Milen Kulev , "Pgsql-Performance ((E-mail))" References: <012d01c6b5b4$6db33680$0a00a8c0@trivadis.com> <20060802004223.GE20401@alvh.no-ip.org> <20060804204450.GS40481@pervasive.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060804204450.GS40481@pervasive.com> User-Agent: Mutt/1.5.12-2006-07-14 X-Virus-Scanned: ClamAV version 0.88.3, clamav-milter version 0.88.3 on projects.commandprompt.com X-Virus-Status: Clean X-Greylist: Sender succeded SMTP AUTH authentication, not delayed by milter-greylist-1.6 (lists.commandprompt.com [192.168.2.159]); Mon, 07 Aug 2006 09:55:40 -0700 (PDT) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=0.856 tagged_above=0 required=5 tests=FORGED_RCVD_HELO, RCVD_IN_NJABL_PROXY X-Spam-Level: X-Archive-Number: 200608/75 X-Sequence-Number: 20260 Jim C. Nasby wrote: > On Tue, Aug 01, 2006 at 08:42:23PM -0400, Alvaro Herrera wrote: > > Most likely ext3 was used on the default configuration, which logs data > > operations as well as metadata, which is what XFS logs. I don't think > > I've seen any credible comparison between XFS and ext3 with the > > metadata-only journal option. > > > > On the other hand I don't think it makes sense to journal data on a > > PostgreSQL environment. Metadata is enough, given that we log data on > > WAL anyway. > > Actually, according to http://en.wikipedia.org/wiki/Ext3 the default > journalling option for ext3 isn't to journal the data (which is actually > data=journal), but to wait until the data is written before considering > the metadata to be committed (data=ordered). Well, we don't need the data to be written before considering metadata committed. data=writeback is enough for partitions to be dedicated to PGDATA. Not sure what other FSs do on this front but the ext3 default leans towards safe rather than speedy. -- Alvaro Herrera http://www.CommandPrompt.com/ The PostgreSQL Company - Command Prompt, Inc.