From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932364AbWDZSI4 (ORCPT ); Wed, 26 Apr 2006 14:08:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932370AbWDZSI4 (ORCPT ); Wed, 26 Apr 2006 14:08:56 -0400 Received: from mail1.skjellin.no ([80.239.42.67]:21226 "EHLO mx1.skjellin.no") by vger.kernel.org with ESMTP id S932364AbWDZSIz (ORCPT ); Wed, 26 Apr 2006 14:08:55 -0400 Message-ID: <444FB742.40604@tomt.net> Date: Wed, 26 Apr 2006 20:09:06 +0200 From: Andre Tomt User-Agent: Thunderbird 1.5.0.2 (Windows/20060308) MIME-Version: 1.0 To: linux-kernel@vger.kernel.org CC: Nick Warne , Jens Axboe Subject: Re: scheduler question 2.6.16.x References: <200604251905.19004.nick@linicks.net> <20060425181530.GQ4102@suse.de> <200604251933.48363.nick@linicks.net> In-Reply-To: <200604251933.48363.nick@linicks.net> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Nick Warne wrote: > On Tuesday 25 April 2006 19:15, Jens Axboe wrote: > >>> But I can build both in... so I guess then the kernel decides what is >>> the best to use? Or should it be so I am only allowed to select one >>> or the other and allowing both is an oversight? >> See the option no more than two lines down from that, default io >> scheduler. Also see Documentation/block/switching-sched.txt and/or >> Documentation/kernel-parameters.txt (elevator=) section. > > Hi Jens, > > I haven't got the switching-sched.txt, although I found a sched-design.txt... > but what I meant was if I select whatever default, do/can I still need to > select either/or scheduler? > > i.e. why doesn't 'default selection option' only allow that scheduler to be > selected? That would be a artificial (and silly!) limit - the io-scheduler is pluggable and selectable at boot, you can even change it at run time at a per block device level. See the elevator= boot option and /sys/block//queue/scheduler