Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 11 Jul 2001 19:46:57 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 11 Jul 2001 19:46:47 -0400 Received: from node-cffb9242.powerinter.net ([207.251.146.66]:39918 "HELO switchmanagement.com") by vger.kernel.org with SMTP id ; Wed, 11 Jul 2001 19:46:30 -0400 Message-ID: <3B4CE556.9000608@switchmanagement.com> Date: Wed, 11 Jul 2001 16:46:30 -0700 From: Brian Strand Organization: Switch Management User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:0.9.2) Gecko/20010628 X-Accept-Language: en-us MIME-Version: 1.0 To: Lance Larsh CC: Andrea Arcangeli , linux-kernel@vger.kernel.org Subject: Re: 2x Oracle slowdown from 2.2.16 to 2.4.4 In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Lance Larsh wrote: >On Wed, 11 Jul 2001, Brian Strand wrote: > >>Our Oracle configuration is on reiserfs on lvm on Mylex. >> >I can pretty much tell you it's the reiser+lvm combination that is hurting >you here. At the 2.5 kernel summit a few months back, I reported that > Why did it get so much worse going from 2.2.16 to 2.4.4, with an otherwise-identical configuration? We had reiserfs+lvm under 2.2.16 too. > >some of our servers experienced as much as 10-15x slowdown after we moved >to 2.4. As it turned out, the problem was that the new servers (with >identical hardware to the old servers) were configured to use reiser+lvm, >whereas the older servers were using ext2 without lvm. When we rebuilt >the new servers with ext2 alone, the problem disappeared. (Note that we >also tried reiserfs without lvm, which was 5-6x slower than ext2 without >lvm.) > >I ran lots of iozone tests which illustrated a huge difference in write >throughput between reiser and ext2. Chris Mason sent me a patch which >improved the reiser case (removing an unnecessary commit), but it was >still noticeably slower than ext2. Therefore I would recommend that >at this time reiser should not be used for Oracle database files. > How do ext2+lvm, rawio+lvm, ext2 w/o lvm, and rawio w/o lvm compare in terms of Oracle performance? I am going to try a migration if 2.4.6 doesn't make everything better; do you have any suggestions as to the relative performance of each strategy? Thanks, Brian - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/