Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762765AbZD3NVX (ORCPT ); Thu, 30 Apr 2009 09:21:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1761135AbZD3NVM (ORCPT ); Thu, 30 Apr 2009 09:21:12 -0400 Received: from g4t0016.houston.hp.com ([15.201.24.19]:34875 "EHLO g4t0016.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756355AbZD3NVL (ORCPT ); Thu, 30 Apr 2009 09:21:11 -0400 Message-ID: <49F9A5BA.9030100@hp.com> Date: Thu, 30 Apr 2009 09:20:58 -0400 From: "Alan D. Brunelle" User-Agent: Thunderbird 2.0.0.21 (X11/20090409) MIME-Version: 1.0 To: Andrea Righi CC: Paul Menage , Balbir Singh , Gui Jianfeng , KAMEZAWA Hiroyuki , agk@sourceware.org, akpm@linux-foundation.org, axboe@kernel.dk, baramsori72@gmail.com, Carl Henrik Lunde , dave@linux.vnet.ibm.com, Divyesh Shah , eric.rannaud@gmail.com, fernando@oss.ntt.co.jp, Hirokazu Takahashi , Li Zefan , matt@bluehost.com, dradford@bluehost.com, ngupta@google.com, randy.dunlap@oracle.com, roberto@unbit.it, Ryo Tsuruta , Satoshi UCHIDA , subrata@linux.vnet.ibm.com, yoshikawa.takuya@oss.ntt.co.jp, containers@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/9] cgroup: io-throttle controller (v13) References: <1239740480-28125-1-git-send-email-righi.andrea@gmail.com> In-Reply-To: <1239740480-28125-1-git-send-email-righi.andrea@gmail.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1293 Lines: 33 Hi Andrea - FYI: I ran a simple test using this code to try and gauge the overhead incurred by enabling this technology. Using a single 400GB volume split into two 200GB partitions I ran two processes in parallel performing a mkfs (ext2) on each partition. First w/out cgroup io-throttle and then with it enabled (with each task having throttling enabled to 400MB/second (much, much more than the device is actually capable of doing)). The idea here is to see the base overhead of just having the io-throttle code in the paths. Doing 30 runs of each (w/out & w/ io-throttle enabled) shows very little difference (time in seconds) w/out: min=80.196 avg=80.585 max=81.030 sdev=0.215 spread=0.834 with: min=80.402 avg=80.836 max=81.623 sdev=0.327 spread=1.221 So only around 0.3% overhead - and that may not be conclusive with the standard deviations seen. -- FYI: The test was run on 2.6.30-rc1+your patches on a 16-way x86_64 box (128GB RAM) plus a single FC volume off of a 1Gb FC RAID controller. Regards, Alan D. Brunelle Hewlett-Packard -- 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/