Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756322AbXISHvS (ORCPT ); Wed, 19 Sep 2007 03:51:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753280AbXISHvH (ORCPT ); Wed, 19 Sep 2007 03:51:07 -0400 Received: from mail.gmx.net ([213.165.64.20]:37903 "HELO mail.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752426AbXISHvG (ORCPT ); Wed, 19 Sep 2007 03:51:06 -0400 X-Authenticated: #14349625 X-Provags-ID: V01U2FsdGVkX19vkDNxMlNvIBlzj+zfpsbRAngiUeAC3h2B+afr37 9J95o2wBXXR/hT Subject: Re: [git] CFS-devel, group scheduler, fixes From: Mike Galbraith To: Tong Li Cc: Ingo Molnar , dimm , linux-kernel@vger.kernel.org, Srivatsa Vaddagiri , Peter Zijlstra In-Reply-To: <1190183324.9737.7.camel@Homer.simpson.net> References: <1190144190.5204.24.camel@earth> <20070918201622.GA1632@elte.hu> <1190183324.9737.7.camel@Homer.simpson.net> Content-Type: text/plain Date: Wed, 19 Sep 2007 09:51:01 +0200 Message-Id: <1190188261.9185.21.camel@Homer.simpson.net> Mime-Version: 1.0 X-Mailer: Evolution 2.8.2 Content-Transfer-Encoding: 7bit X-Y-GMX-Trusted: 0 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2870 Lines: 70 On Wed, 2007-09-19 at 08:28 +0200, Mike Galbraith wrote: > Greetings, > > On Tue, 2007-09-18 at 23:03 -0700, Tong Li wrote: > > This patch attempts to improve CFS's SMP global fairness based on the new > > virtual time design. > > > > Removed vruntime adjustment in set_task_cpu() as it skews global fairness. > > Since I'm (still) encountering Xorg latency issues (which go away if > load is hefty instead of light) even with that migration adjustment and > synchronization, and am having difficulty nailing it down to a specific > event, I'll test this immediately. (had to apply manually to freshly pulled tree) Drat. This didn't cure the latency hits with a Xorg at nice -5 running with a make -j2 at nice 0, but seems to have reinstated a latency issue which was previously cured. Xorg 1 sec. max latency samples: (trimmed to only show >20ms latencies) se.wait_max : 23343582 se.wait_max : 20119460 se.wait_max : 20771573 se.wait_max : 21084567 se.wait_max : 31338500 se.wait_max : 35368148 se.wait_max : 39199642 se.wait_max : 22889062 se.wait_max : 40285501 se.wait_max : 21002720 se.wait_max : 21002266 se.wait_max : 21680578 se.wait_max : 22012913 se.wait_max : 94646331 se.wait_max : 29003693 se.wait_max : 20812613 (boot with maxcpus=1 or nail X+make to one cpu and these latencies are gone, so it does seem to be the migration logic - why i was so interested in testing your patch) The scenario which was previously cured was this: taskset -c 1 nice -n 0 ./massive_intr 2 9999 taskset -c 1 nice -n 5 ./massive_intr 2 9999 click link (http://pages.cs.wisc.edu/~shubu/talks/cachescrub-prdc2004.ppt) to bring up browser and OpenOffice Impress. Xorg (at nice -5 + above scenario) latency samples: se.wait_max : 57985337 se.wait_max : 25163510 se.wait_max : 37005538 se.wait_max : 66986511 se.wait_max : 53990868 se.wait_max : 80976761 se.wait_max : 96967501 se.wait_max : 80989254 se.wait_max : 53990897 se.wait_max : 181963905 se.wait_max : 85985181 -Mike - 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/