Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261641AbVEDLxV (ORCPT ); Wed, 4 May 2005 07:53:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261675AbVEDLxU (ORCPT ); Wed, 4 May 2005 07:53:20 -0400 Received: from mailhub.sw.ru ([195.214.233.200]:55338 "EHLO relay.sw.ru") by vger.kernel.org with ESMTP id S261641AbVEDLw1 (ORCPT ); Wed, 4 May 2005 07:52:27 -0400 Message-ID: <4278B772.5080806@sw.ru> Date: Wed, 04 May 2005 15:52:18 +0400 From: Kirill Korotaev User-Agent: Mozilla/5.0 (X11; U; Linux i686; ru-RU; rv:1.2.1) Gecko/20030426 X-Accept-Language: ru-ru, en MIME-Version: 1.0 To: Carlos Carvalho CC: linux-kernel@vger.kernel.org Subject: Re: problem with nice values and cpu consumption in 2.6.11-5 References: <17015.35256.12650.37887@fisica.ufpr.br> In-Reply-To: <17015.35256.12650.37887@fisica.ufpr.br> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1553 Lines: 35 This is a real problem with O(1)-scheduler in 2.6... :( The only workaround for you right now is to run 2.4 or move to some type of virtualization solutions with fair cpu scheduler... Kirill > Look at this cpu usage in a two-processor machine: > > 893 user1 39 19 7212 5892 492 R 99.7 1.1 3694:29 mi41 > 1118 user2 25 0 155m 61m 624 R 50.0 12.3 857:54.18 b170-se.x > 1186 user3 25 0 155m 62m 640 R 50.2 12.3 103:25.22 b170-se.x > > The job with nice 19 seems to be using 100% of cpu time while the > other two nice 0 jobs share a single processor with 50% only. This is > persistent, not a transient. I did a kill -STOP to the nice 19 job and > a kill -CONT, and for a while it decreased the cpu usage but later > returned to the above. > > This is with kernel 2.6.11-5 and top 3.2.5. What's the reason for this > (apparent??) mis-behavior and how can I correct it? This is important > because the machine is used for number-crunching and users get really > upset when they don't get the expected share of cpu time... > - > 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/ > - 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/