From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752328AbWFMFpp (ORCPT ); Tue, 13 Jun 2006 01:45:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752329AbWFMFpo (ORCPT ); Tue, 13 Jun 2006 01:45:44 -0400 Received: from ns.virtualhost.dk ([195.184.98.160]:18485 "EHLO virtualhost.dk") by vger.kernel.org with ESMTP id S1752327AbWFMFpo (ORCPT ); Tue, 13 Jun 2006 01:45:44 -0400 Date: Tue, 13 Jun 2006 07:46:10 +0200 From: Jens Axboe To: Vishal Patil Cc: Linux Kernel Mailing List , Jan Engelhardt Subject: Re: CSCAN vs CFQ I/O scheduler benchmark results Message-ID: <20060613054609.GR4420@suse.de> References: <4745278c0606091230g1cff8514vc6ad154acb62e341@mail.gmail.com> <4745278c0606091915n3ed7563do505664c4f8070f81@mail.gmail.com> <20060611185854.GF13556@suse.de> <4745278c0606111647g7ca1392bjb46936f69d6b668d@mail.gmail.com> <20060612064136.GB4420@suse.de> <4745278c0606121038y7fcdab2q33a9065e9071938b@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4745278c0606121038y7fcdab2q33a9065e9071938b@mail.gmail.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 12 2006, Vishal Patil wrote: > Jens > > Could you let me know what tests would be fair to make comparsion > between the I/O schedulers? Thanks. Depends on what you want to test, of course! I can't give you an answer on that. The thing about IO schedulers is that it's easy to provide good throughput or good latency, but hard to do both. The tests you did so far have x processes doing the same thing. Try something that has eg an async writer going full throttle, and then a/some sync readers. -- Jens Axboe