From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932975Ab1IHNrU (ORCPT ); Thu, 8 Sep 2011 09:47:20 -0400 Received: from minas.ics.muni.cz ([147.251.4.40]:45028 "EHLO minas.ics.muni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932789Ab1IHNrT (ORCPT ); Thu, 8 Sep 2011 09:47:19 -0400 X-Greylist: delayed 1079 seconds by postgrey-1.27 at vger.kernel.org; Thu, 08 Sep 2011 09:47:18 EDT Date: Thu, 8 Sep 2011 15:27:56 +0200 From: Lukas Hejtmanek To: Kiyoshi Ueda Cc: "Jun'ichi Nomura" , agk@redhat.com, linux-kernel@vger.kernel.org Subject: Re: request baset device mapper in Linux Message-ID: <20110908132756.GT31717@ics.muni.cz> References: <20110720082640.GZ7561@ics.muni.cz> <4E280964.6070000@ct.jp.nec.com> <20110721132627.GY7561@ics.muni.cz> <4E291F28.2040609@ct.jp.nec.com> <20110722081903.GB7561@ics.muni.cz> <4E2A7806.1060601@ce.jp.nec.com> <20110724221619.GM16487@ics.muni.cz> <4E367256.8020206@ct.jp.nec.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-2 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <4E367256.8020206@ct.jp.nec.com> X-echelon: NSA, CIA, CI5, MI5, FBI, KGB, BIS, Plutonium, Bin Laden, bomb User-Agent: Mutt/1.5.21 (2010-09-15) X-Muni-Spam-TestIP: 147.251.17.147 X-Muni-Envelope-From: xhejtman@anubis.ics.muni.cz X-Muni-Virus-Test: Clean X-Greylist: Sender succeeded SMTP AUTH authentication, not delayed by milter-greylist-3.0 (minas.ics.muni.cz [147.251.4.35]); Thu, 08 Sep 2011 15:29:04 +0200 (CEST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Aug 01, 2011 at 06:31:02PM +0900, Kiyoshi Ueda wrote: > Hi Lukas, > > Lukas Hejtmanek wrote: > > On Sat, Jul 23, 2011 at 04:28:06PM +0900, Jun'ichi Nomura wrote: > >> As Kiyoshi suggested, it is important to know whether this > >> problem occurs with the latest kernel. > >> So if you could try 3.0, it would be very helpful. > > > > so, do I need to check recent kernel as the patch works for me? > > Yes, please. > (Unfortunately my storage has been broken today :-<) > > CPU usage seems to be one of the reasons for your case, but I > still cannot understand why memory pressure is needed. > I want to know your problem also occurs on 3.0 without the patch. Well, I tried 3.0.3 kernel. It is not so bad as 2.6.32.36, but it is not as good as the same kernel with your patch. CPU load is caused by ksoftirqd (30-40%) and kworker (30%). Overal speed is about 2.5GB/s. With your patch I can reach 2.8-2.9GB/s. -- Lukáš Hejtmánek