From: Valerie Clement Subject: Re: Performance degradation with FFSB between 2.6.20 and 2.6.21-rc7 Date: Thu, 19 Apr 2007 14:45:02 +0200 Message-ID: <4627644E.7010002@bull.net> References: <462622F8.10107@bull.net> <20070419090346.GE20928@kernel.dk> <462736FC.3090902@bull.net> <20070419115840.GA11780@kernel.dk> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: ext4 development , Andrew Morton , Linux Kernel Mailing List To: Jens Axboe Return-path: Received: from ecfrec.frec.bull.fr ([129.183.4.8]:46873 "EHLO ecfrec.frec.bull.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S637744AbXDSMpv (ORCPT ); Thu, 19 Apr 2007 08:45:51 -0400 In-Reply-To: <20070419115840.GA11780@kernel.dk> Sender: linux-ext4-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org Jens Axboe wrote: > On Thu, Apr 19 2007, Valerie Clement wrote: >> Jens Axboe wrote: >>> Please tell me how you are running ffsb, and also please include a >>> dmessg from a booted system. >>> >> Hi, >> our mails crossed! please see my response to Andrew. >> You could reproduce the problem with dd command as suggested, it's m= ore=20 >> easy. >> I'm sending you the dmesg info. For my tests I used the scsci sdc de= vice. >=20 > Thanks, it does. Can you try one thing for me? If you run the test on > sdc, try doing: >=20 > # echo 64 > /sys/block/sdc/queue/iosched/quantum >=20 > and repeat the test. >=20 OK, that's done. With the change of quantum, the throughput scores are now a little bit=20 better in 2.6.21 than in 2.6.20. Val=E9rie