Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754308AbZJCKrc (ORCPT ); Sat, 3 Oct 2009 06:47:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753297AbZJCKrc (ORCPT ); Sat, 3 Oct 2009 06:47:32 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:51494 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752046AbZJCKrb (ORCPT ); Sat, 3 Oct 2009 06:47:31 -0400 Date: Sat, 3 Oct 2009 12:47:23 +0200 From: Ingo Molnar To: drago01 , Peter Zijlstra , Mike Galbraith Cc: kernel list , mingo@redhat.com, Chuck Ebbert Subject: Re: sched regression introduced by NO_NEW_FAIR_SLEEPERS Message-ID: <20091003104723.GC15919@elte.hu> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.5 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3416 Lines: 77 * drago01 wrote: > On Sun, Sep 27, 2009 at 9:47 PM, drago01 wrote: > > Hi, > > > > Chuck has backported some scheduler patches from 2.6.32 to the fedora kernel. > > > > I did the following test to test the new scheduler (cpu is a core i7 > > 920 4 cores + HT). > > > > run 8 "md5sum /dev/urandom" task and try to use the desktop (compiz). > > > > The result was that moving windows or rotating the cube is very slow. > > (same happens with pure metacity but is is worse in compiz). > > > > Mounting debugfs and doing "echo NEW_FAIR_SLEEPERS > sched_features" > > results into a useable desktop while the 8 md5sum tasks are running > > (ie. the system behaves as if they where not running at all from an > > interactivity pov). > > > > > > P.S: please CC me when replying. > > > > With "NEW_FAIR_SLEEPERS" I can even run 100(!) "md5sum" task without > any effect on interactivity. (still have not found a number of tasks > needed to make the system unresponsive as with 8 with > "NO_NEW_FAIR_SLEEPERS". Can you try the latest -tip tree please: http://people.redhat.com/mingo/tip.git/README There we default to FAIR_SLEEPERS + GENTLE_FAIR_SLEEPERS - which should give much of the new-fair-sleepers advantage. There's also a new tool, 'perf sched', which you can install via: cd tools/perf/ make -j install And use like this to measure latencies in the system: $ perf sched record sleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.059 MB perf.data (~2563 samples) ] $ perf sched latency ----------------------------------------------------------------------------------------- Task | Runtime ms | Switches | Average delay ms | Maximum delay ms | ----------------------------------------------------------------------------------------- events/12:47 | 0.007 ms | 1 | avg: 0.054 ms | max: 0.054 ms | events/2:37 | 0.128 ms | 1 | avg: 0.016 ms | max: 0.016 ms | at-spi-registry:3292 | 0.752 ms | 20 | avg: 0.015 ms | max: 0.023 ms | Xorg:3161 | 0.519 ms | 20 | avg: 0.015 ms | max: 0.024 ms | perf:19070 | 21.241 ms | 5 | avg: 0.012 ms | max: 0.019 ms | events/1:36 | 0.009 ms | 1 | avg: 0.009 ms | max: 0.009 ms | hald-addon-stor:2790 | 0.204 ms | 9 | avg: 0.009 ms | max: 0.011 ms | scsi_eh_5:1072 | 0.200 ms | 12 | avg: 0.009 ms | max: 0.009 ms | events/0:35 | 0.007 ms | 1 | avg: 0.008 ms | max: 0.008 ms | ksoftirqd/12:28 | 0.088 ms | 5 | avg: 0.005 ms | max: 0.009 ms | sleep:19071 | 0.668 ms | 3 | avg: 0.005 ms | max: 0.008 ms | migration/13:29 | 0.000 ms | 1 | avg: 0.003 ms | max: 0.003 ms | ----------------------------------------------------------------------------------------- TOTAL: | 23.824 ms | 79 | --------------------------------------------------- Thanks, 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/