From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Moyer Subject: Re: [PATCH 0/4 v4] ext3/4: enhance fsync performance when using CFQ Date: Wed, 26 May 2010 11:33:17 -0400 Message-ID: References: <1274206820-17071-1-git-send-email-jmoyer@redhat.com> <20100519105706.8821.A69D9226@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-kernel@vger.kernel.org, linux-ext4@vger.kernel.org, jens.axboe@oracle.com, vgoyal@redhat.com To: KOSAKI Motohiro Return-path: Received: from mx1.redhat.com ([209.132.183.28]:14946 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756676Ab0EZPdY (ORCPT ); Wed, 26 May 2010 11:33:24 -0400 In-Reply-To: <20100519105706.8821.A69D9226@jp.fujitsu.com> (KOSAKI Motohiro's message of "Wed, 19 May 2010 11:05:20 +0900 (JST)") Sender: linux-ext4-owner@vger.kernel.org List-ID: KOSAKI Motohiro writes: > Hi Jeff, > >> This patch series addresses a performance problem experienced when running >> io_zone with small file sizes (from 4KB up to 8MB) and including fsync in >> the timings. A good example of this would be the following command line: >> iozone -s 64 -e -f /mnt/test/iozone.0 -i 0 >> As the file sizes get larger, the performance improves. By the time the >> file size is 16MB, there is no difference in performance between runs >> using CFQ and runs using deadline. The storage in my testing was a NetApp >> array connected via a single fibre channel link. When testing against a >> single SATA disk, the performance difference is not apparent. > > offtopic: > > Can this patch help to reduce a pain of following much small files issue? > > http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=578635 Perhaps. I don't have a debian system handy to test that, though. Cheers, Jeff