X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (av.hub.org [200.46.204.144]) by postgresql.org (Postfix) with ESMTP id 404F99DC997 for ; Fri, 6 Jan 2006 10:00:12 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 20339-01 for ; Fri, 6 Jan 2006 10:00:11 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey- Received: from mailhost.intellivid.com (mailhost.intellivid.com [64.32.200.11]) by postgresql.org (Postfix) with ESMTP id F14699DC949 for ; Fri, 6 Jan 2006 10:00:03 -0400 (AST) Received: from spectre.intellivid.com (spectre.intellivid.com [192.168.2.68]) (using TLSv1 with cipher RC4-MD5 (128/128 bits)) (Client did not present a certificate) by newmail.intellivid.com (Postfix) with ESMTP id 01C78F18111; Fri, 6 Jan 2006 09:00:07 -0500 (EST) Subject: Re: improving write performance for logging From: Ian Westmacott To: "Jim C. Nasby" Cc: pgsql-performance@postgresql.org In-Reply-To: <20060106010822.GK43311@pervasive.com> References: <43BB0C5C.8020207@computer.org> <1136382865.24450.7.camel@spectre.intellivid.com> <7.0.1.0.2.20060104092139.01c37da0@earthlink.net> <1136390438.24450.49.camel@spectre.intellivid.com> <20060106010822.GK43311@pervasive.com> Content-Type: text/plain Organization: Intellivid Corp. Date: Fri, 06 Jan 2006 09:00:06 -0500 Message-Id: <1136556006.31602.5.camel@spectre.intellivid.com> Mime-Version: 1.0 X-Mailer: Evolution 2.4.1 Content-Transfer-Encoding: 7bit X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, score=0.12 required=5 tests=[AWL=0.120] X-Spam-Score: 0.12 X-Spam-Level: X-Archive-Number: 200601/37 X-Sequence-Number: 16515 On Thu, 2006-01-05 at 19:08 -0600, Jim C. Nasby wrote: > On Wed, Jan 04, 2006 at 11:00:38AM -0500, Ian Westmacott wrote: > > The WAL is a 2-spindle (SATA) RAID0 with its own controller (ext3). > > The tables are on a 10-spindle (SCSI) RAID50 with dual U320 > > controllers (XFS). This is overkill for writing and querying the data, > > but we need to constantly ANALYZE and VACUUM in the > > background without interrupting the inserts (the app is 24x7). The > > databases are 4TB, so these operations can be lengthy. > > How come you're using RAID50 instead of just RAID0? Or was WAL being on > RAID0 a typo? We use RAID50 instead of RAID0 for the tables for some fault-tolerance. We use RAID0 for the WAL for performance. I'm missing the implication of the question... -- Ian Westmacott Intellivid Corp.