From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751161AbWFKXrJ (ORCPT ); Sun, 11 Jun 2006 19:47:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751176AbWFKXrJ (ORCPT ); Sun, 11 Jun 2006 19:47:09 -0400 Received: from wx-out-0102.google.com ([66.249.82.196]:47342 "EHLO wx-out-0102.google.com") by vger.kernel.org with ESMTP id S1751161AbWFKXrI (ORCPT ); Sun, 11 Jun 2006 19:47:08 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=FLBKMzH6qbTd+gZcaVbqley8dmc8+uLy1Wyx7ZsZ3nxqoOq3dMUi02b0Ezo/oP1iYgXm69TDrkt9nDt4358rUvFg4jpLs81bOSU8BNX5Im5BCfM6dtU4mXHzVRLJow913B2JkalgKa1/0h4qbVl5d2IOxfbxlyfoHaQhIlHWfLM= Message-ID: <4745278c0606111647g7ca1392bjb46936f69d6b668d@mail.gmail.com> Date: Sun, 11 Jun 2006 19:47:07 -0400 From: "Vishal Patil" To: "Jens Axboe" Subject: Re: CSCAN vs CFQ I/O scheduler benchmark results Cc: "Linux Kernel Mailing List" , "Jan Engelhardt" In-Reply-To: <20060611185854.GF13556@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <4745278c0606091230g1cff8514vc6ad154acb62e341@mail.gmail.com> <4745278c0606091915n3ed7563do505664c4f8070f81@mail.gmail.com> <20060611185854.GF13556@suse.de> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Jan I ran the performance benchmark on an IBM machine with the following harddrive attached to it. cat /proc/ide/hda/model ST340014A Also note the CSCAN implementation is using rbtrees due which the time complexity of the different operations is O(log(n)) and not O(n) and that might be the reason that we are getting good values for specially in case of sequential writes and the random workloads. I will try making measurements using 2.6.17-rc6-gitX until next weekend. Thanks for help and inputs folks. - Vishal On 6/11/06, Jens Axboe wrote: > On Fri, Jun 09 2006, Vishal Patil wrote: > > The machine configuation is as follows > > CPU: Intel(R) Pentium(R) 4 CPU 2.80GHz > > Memory: 1027500 KB (1 GB) > > Filesystem: ext3 > > Kernel: 2.6.16.2 > > You don't mention the storage used, which is quite relevant. > > If you have the time, please rerun with 2.6.17-rc6-gitX latest. Although > I'm not sure why you think CSCAN is a good scheduling algorithm, in > general it may be fine but there are trivial non-root 'dos' attacks. Any > of the non-noop Linux io schedulers is a better choice imo. > > -- > Jens Axboe > > -- Success is mainly about failing a lot.