Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1945971AbWANBr1 (ORCPT ); Fri, 13 Jan 2006 20:47:27 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1945973AbWANBr1 (ORCPT ); Fri, 13 Jan 2006 20:47:27 -0500 Received: from smtp.osdl.org ([65.172.181.4]:36498 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1945971AbWANBr0 (ORCPT ); Fri, 13 Jan 2006 20:47:26 -0500 Date: Fri, 13 Jan 2006 17:49:14 -0800 From: Andrew Morton To: cmm@us.ibm.com Cc: seelam@cs.utep.edu, linux-kernel@vger.kernel.org, ext2-devel@lists.sourceforge.net, Jens Axboe Subject: Re: Fall back io scheduler for 2.6.15? Message-Id: <20060113174914.7907bf2c.akpm@osdl.org> In-Reply-To: <1137201135.4353.81.camel@localhost.localdomain> References: <1112673094.14322.10.camel@mindpipe> <1112971236.1975.104.camel@sisko.sctweedie.blueyonder.co.uk> <1112983801.10605.32.camel@dyn318043bld.beaverton.ibm.com> <1113220089.2164.52.camel@sisko.sctweedie.blueyonder.co.uk> <1113244710.4413.38.camel@localhost.localdomain> <1113249435.2164.198.camel@sisko.sctweedie.blueyonder.co.uk> <1113288087.4319.49.camel@localhost.localdomain> <1113304715.2404.39.camel@sisko.sctweedie.blueyonder.co.uk> <1113348434.4125.54.camel@dyn318043bld.beaverton.ibm.com> <1113388142.3019.12.camel@sisko.sctweedie.blueyonder.co.uk> <1114207837.7339.50.camel@localhost.localdomain> <1114659912.16933.5.camel@mindpipe> <1114715665.18996.29.camel@localhost.localdomain> <1136935562.4901.41.camel@dyn9047017067.beaverton.ibm.com> <20060110212551.411a766d.akpm@osdl.org> <1137007032.4395.24.camel@localhost.localdomain> <20060111114303.45540193.akpm@osdl.org> <1137201135.4353.81.camel@localhost.localdomain> X-Mailer: Sylpheed version 1.0.0 (GTK+ 1.2.10; i386-vine-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 944 Lines: 23 Mingming Cao wrote: > > On 2.6.14, the > fall back io scheduler (if the chosen io scheduler is not found) is set > to the default io scheduler (anticipatory, in this case), but since > 2.6.15-rc1, this semanistic is changed to fall back to noop. OK. And I assume that AS wasn't compiled, so that's why it fell back? I actually thought that elevator= got removed, now we have /sys/block/sda/queue/scheduler. But I guess that's not very useful with CONFIG_SYSFS=n. > Is there any reason to fall back to noop instead of as? It seems > anticipatory is much better than noop for ext3 with large sequential > write tests (i.e, 1G dd test) ... I suspect that was an accident. Jens? - 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/