From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933273AbXGLMkG (ORCPT ); Thu, 12 Jul 2007 08:40:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755362AbXGLMjy (ORCPT ); Thu, 12 Jul 2007 08:39:54 -0400 Received: from pool-70-109-119-137.alb.east.verizon.net ([70.109.119.137]:50894 "EHLO gaimboi.tmr.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754667AbXGLMjx (ORCPT ); Thu, 12 Jul 2007 08:39:53 -0400 Message-ID: <46962173.2050603@tmr.com> Date: Thu, 12 Jul 2007 08:41:23 -0400 From: Bill Davidsen Organization: TMR Associates Inc, Schenectady NY User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.0.8) Gecko/20061105 SeaMonkey/1.0.6 MIME-Version: 1.0 To: Ingo Molnar CC: linux-kernel@vger.kernel.org, Linus Torvalds , Andrew Morton , Arjan van de Ven , Thomas Gleixner , Dmitry Adamushko , Srivatsa Vaddagiri Subject: Re: [patch] CFS scheduler, -v19 References: <20070706173319.GA2356@elte.hu> <1184054902.12336.19.camel@Homer.simpson.net> <469512C1.6090406@tmr.com> <20070711205556.GA27266@elte.hu> In-Reply-To: <20070711205556.GA27266@elte.hu> 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 Ingo Molnar wrote: > * Bill Davidsen wrote: > > >>> I've taken mainline git tree (freshly integrated CFS!) out for a >>> multimedia spin. I tested watching movies and listenign to music in >>> the presence of various sleep/burn loads, pure burn loads, and mixed >>> loads. All was peachy here.. I saw no frame drops or sound skips or >>> other artifacts under any load where the processor could possibly >>> meet demand. >>> >> I would agree with preliminary testing, save that if you get a lot of >> processes updating the screen at once, there seems to be a notable >> case of processes getting no CPU for 100-300ms, followed by a lot of >> CPU. >> >> I see this clearly with the "glitch1" test with four scrolling xterms >> and glxgears, but also watching videos with little busy processes on >> the screen. The only version where I never see this in test or with >> real use is cfs-v13. >> > > just as a test, does this go away if you: > > renice -20 pidof `Xorg` > > i.e. is this connected to the way X is scheduled? > > Partial answer: -10 didn't help with v16, I'll try more boost ASAP, but power has been spotty in upstate NY, 20k+ customers with none and the rest of us subject to "load shedding" with zero warning, and the test machines have UPS but no generator, so I hesitate to use them while power is unstable. > Another thing to check would be whether it goes away if you set the > granularity to some really finegrained value: > > echo 0 > /proc/sys/kernel/sched_wakeup_granularity_ns > echo 500000 > /proc/sys/kernel/sched_granularity_ns > > this really pushes things - but it tests the theory whether this is > related to granularity. > Will do, you suggested dropping sched_granularity_ns to 1000000 earlier, and that didn't do it, but I didn't change the wakeup, and will test these values later today. -- bill davidsen CTO TMR Associates, Inc Doing interesting things with small computers since 1979