From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1422723AbXDRJfK (ORCPT ); Wed, 18 Apr 2007 05:35:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1422721AbXDRJfK (ORCPT ); Wed, 18 Apr 2007 05:35:10 -0400 Received: from mail15.syd.optusnet.com.au ([211.29.132.196]:52644 "EHLO mail15.syd.optusnet.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1422723AbXDRJfI (ORCPT ); Wed, 18 Apr 2007 05:35:08 -0400 From: Con Kolivas To: Nick Piggin Subject: Re: [Announce] [patch] Modular Scheduler Core and Completely Fair Scheduler [CFS] Date: Wed, 18 Apr 2007 19:33:56 +1000 User-Agent: KMail/1.9.5 Cc: Ingo Molnar , Andy Whitcroft , linux-kernel@vger.kernel.org, Linus Torvalds , Andrew Morton , Mike Galbraith , Arjan van de Ven , Thomas Gleixner , Steve Fox , Nishanth Aravamudan References: <20070413202100.GA9957@elte.hu> <20070417095900.GB25553@elte.hu> <20070418085525.GA21194@wotan.suse.de> In-Reply-To: <20070418085525.GA21194@wotan.suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200704181933.57057.kernel@kolivas.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wednesday 18 April 2007 18:55, Nick Piggin wrote: > On Tue, Apr 17, 2007 at 11:59:00AM +0200, Ingo Molnar wrote: > > * Nick Piggin wrote: > > > 2.6.21-rc7-cfs-v2 > > > 534.80user 30.92system 2:23.64elapsed 393%CPU > > > 534.75user 31.01system 2:23.70elapsed 393%CPU > > > 534.66user 31.07system 2:23.76elapsed 393%CPU > > > 534.56user 30.91system 2:23.76elapsed 393%CPU > > > 534.66user 31.07system 2:23.67elapsed 393%CPU > > > 535.43user 30.62system 2:23.72elapsed 393%CPU > > > > Thanks for testing this! Could you please try this also with: > > > > echo 100000000 > /proc/sys/kernel/sched_granularity > > 507.68user 31.87system 2:18.05elapsed 390%CPU > 507.99user 31.93system 2:18.09elapsed 390%CPU > 507.46user 31.78system 2:18.03elapsed 390%CPU > 507.68user 31.93system 2:18.11elapsed 390%CPU > 507.63user 31.98system 2:18.01elapsed 390%CPU > 507.83user 31.94system 2:18.28elapsed 390%CPU > > > could you maybe even try a more extreme setting of: > > > > echo 500000000 > /proc/sys/kernel/sched_granularity > > 504.87user 32.13system 2:18.03elapsed 389%CPU > 505.94user 32.29system 2:17.87elapsed 390%CPU > 506.10user 31.90system 2:17.96elapsed 389%CPU > 505.02user 32.02system 2:17.96elapsed 389%CPU > 506.69user 31.96system 2:17.82elapsed 390%CPU > 505.70user 31.84system 2:17.90elapsed 389%CPU > > > Again, for comparison 2.6.21-rc7 mainline: > > 508.87user 32.47system 2:17.82elapsed 392%CPU > 509.05user 32.25system 2:17.84elapsed 392%CPU > 508.75user 32.26system 2:17.83elapsed 392%CPU > 508.63user 32.17system 2:17.88elapsed 392%CPU > 509.01user 32.26system 2:17.90elapsed 392%CPU > 509.08user 32.20system 2:17.95elapsed 392%CPU > > So looking at elapsed time, a granularity of 100ms is just behind the > mainline score. However it is using slightly less user time and > slightly more idle time, which indicates that balancing might have got > a bit less aggressive. > > But anyway, it conclusively shows the efficiency impact of such tiny > timeslices. See test.kernel.org for how (the now defunct) SD was performing on kernbench. It had low latency _and_ equivalent throughput to mainline. Set the standard appropriately on both counts please. -- -ck