Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262406AbUJ0MWV (ORCPT ); Wed, 27 Oct 2004 08:22:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262412AbUJ0MWA (ORCPT ); Wed, 27 Oct 2004 08:22:00 -0400 Received: from relay03.pair.com ([209.68.5.17]:32011 "HELO relay03.pair.com") by vger.kernel.org with SMTP id S262406AbUJ0MTM (ORCPT ); Wed, 27 Oct 2004 08:19:12 -0400 X-pair-Authenticated: 66.190.53.4 Message-ID: <417F923E.9080905@cybsft.com> Date: Wed, 27 Oct 2004 07:19:10 -0500 From: "K.R. Foley" User-Agent: Mozilla Thunderbird 0.8 (X11/20040913) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Ingo Molnar 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 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> <20041027093256.GA19849@elte.hu> In-Reply-To: <20041027093256.GA19849@elte.hu> X-Enigmail-Version: 0.86.1.0 X-Enigmail-Supports: pgp-inline, pgp-mime Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1710 Lines: 43 Ingo Molnar wrote: > * 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? > It appears that most of the time is being consumed in system (~50% vs. ~6%). > > 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. As for the context-switch, I do see this jump up to ~10-11K/sec from ~4-5K/sec and I see this only when I trigger the pauses. > > Ingo > kr - 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/