Return-Path: Received: from air189.startdedicated.com (root@localhost) by orafaq.com (8.11.6/8.11.6) with ESMTP id i12JMCf24411 for ; Mon, 2 Feb 2004 13:22:12 -0600 X-ClientAddr: 206.53.239.180 Received: from turing.freelists.org (freelists-180.iquest.net [206.53.239.180]) by air189.startdedicated.com (8.11.6/8.11.6) with ESMTP id i12JMBo24406 for ; Mon, 2 Feb 2004 13:22:11 -0600 Received: from turing (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 8B777395324; Mon, 2 Feb 2004 14:19:27 -0500 (EST) Received: with ECARTIS (v1.0.0; list oracle-l); Mon, 02 Feb 2004 14:17:54 -0500 (EST) X-Original-To: oracle-l@freelists.org Delivered-To: oracle-l@freelists.org Received: from qescan1.qgraph.com (QESCAN1.qgraph.com [206.158.124.7]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id EE528395A2C for ; Mon, 2 Feb 2004 14:17:34 -0500 (EST) Received: by sxsmtp3.qgraph.com with Internet Mail Service (5.5.2657.72) id ; Mon, 2 Feb 2004 13:24:32 -0600 Message-ID: From: "Jesse, Rich" To: "'oracle-l@freelists.org'" Subject: RE: RAID 1 or 10 for Oracle redo/control files? Date: Mon, 2 Feb 2004 13:24:08 -0600 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2657.72) Content-type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit X-archive-position: 582 X-ecartis-version: Ecartis v1.0.0 Sender: oracle-l-bounce@freelists.org Errors-To: oracle-l-bounce@freelists.org X-original-sender: Rich.Jesse@qtiworld.com Precedence: normal Reply-To: oracle-l@freelists.org X-list: oracle-l Yes, my mistake in transcribing. I've proposed *four* disks -- two sets of RAID-1, alternating the redos. Rich Rich Jesse System/Database Administrator rich.jesse@qtiworld.com Quad/Tech International, Sussex, WI USA -----Original Message----- From: Tanel Poder [mailto:tanel.poder.003@mail.ee] Sent: Monday, February 02, 2004 12:53 PM To: oracle-l@freelists.org Subject: Re: RAID 1 or 10 for Oracle redo/control files? > I've been asked to prove why the Redos shouldn't be RAID 10, because the > striping should allow for faster writes. I remember reading that this was > nullified by the sequential nature of the writes, but I can't remember where > I saw this. Well, if you have all the logs on since RAID 10, then the IOs caused by archiving a log will be disturbing LGWR writes (causing lot's of extra head movement for disks). This means occassional performance degradation for both ARCH and LGWR processes. But if you have spread your odd redos to one disk set and even ones to another set, then the archiver can copy away the logs without disturbing LGWR at all. This is feasible approach for environments where disk IO on redolog spindles is the bottleneck (btw, your SANs cache may relieve this issue a lot if configured properly). Tanel. ---------------------------------------------------------------- Please see the official ORACLE-L FAQ: http://www.orafaq.com ---------------------------------------------------------------- To unsubscribe send email to: oracle-l-request@freelists.org put 'unsubscribe' in the subject line. -- Archives are at http://www.freelists.org/archives/oracle-l/ FAQ is at http://www.freelists.org/help/fom-serve/cache/1.html -----------------------------------------------------------------