Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262350AbUJ0JeU (ORCPT ); Wed, 27 Oct 2004 05:34:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262349AbUJ0JeU (ORCPT ); Wed, 27 Oct 2004 05:34:20 -0400 Received: from mx1.elte.hu ([157.181.1.137]:3517 "EHLO mx1.elte.hu") by vger.kernel.org with ESMTP id S262350AbUJ0Jb7 (ORCPT ); Wed, 27 Oct 2004 05:31:59 -0400 Date: Wed, 27 Oct 2004 11:32:56 +0200 From: Ingo Molnar To: "K.R. Foley" Cc: linux-kernel@vger.kernel.org, Lee Revell , Rui Nuno Capela , Mark_H_Johnson@Raytheon.com, Bill Huey , Adam Heath , Florian Schmidt , Thomas Gleixner , Michal Schmidt , Fernando Pablo Lopez-Lezcano , Alexander Batyrshin Subject: Re: [patch] Real-Time Preemption, -RT-2.6.9-mm1-V0 Message-ID: <20041027093256.GA19849@elte.hu> References: <20041022133551.GA6954@elte.hu> <20041022155048.GA16240@elte.hu> <20041022175633.GA1864@elte.hu> <20041025104023.GA1960@elte.hu> <417D4B5E.4010509@cybsft.com> <20041025203807.GB27865@elte.hu> <417E2CB7.4090608@cybsft.com> <20041027002455.GC31852@elte.hu> <417F16BB.3030300@cybsft.com> <20041027092453.GA17999@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20041027092453.GA17999@elte.hu> User-Agent: Mutt/1.4.1i X-ELTE-SpamVersion: MailScanner 4.31.6-itk1 (ELTE 1.2) SpamAssassin 2.63 ClamAV 0.73 X-ELTE-VirusStatus: clean X-ELTE-SpamCheck: no X-ELTE-SpamCheck-Details: score=-4.9, required 5.9, autolearn=not spam, BAYES_00 -4.90 X-ELTE-SpamLevel: X-ELTE-SpamScore: -4 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1448 Lines: 31 * Ingo Molnar wrote: > > Still problems with interactive behavior. Running KDE, with top > > running in xterm, scrolling through the menus I get some pauses. When > > the pauses occur I see kdeinit hit the top of the list and sometimes > > consuming 90% or more of a CPU and idle usage drops to 30-40%. I do > > see some latency traces (not really high ones) in the log that were > > generated by kdeinit but I think they were generated prior to when > > these pauses occurred, most likely when logging in. > > is this 90% or more CPU time system (kernel) overhead or userspace > overhead? another thing to watch for is the context-switch rate in vmstat. -V0.3 patches include a hack that include involuntary context-switches (mutex context switches) in the context-switch stat as well. (previously those were reported in a separate field which vmstat didnt pick up.) So if the context-switch rate shots up to above say 100K/sec that is a sure sign of some mutex badness. The livelock scenarios i solved in -V0.3 occasionally generated a more than 500K/sec context-switch rate on a 2GHz box. Having just a couple of thousand per sec isnt by itself a sign of anything unusual. Ingo - 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/