From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763211AbYEBLLH (ORCPT ); Fri, 2 May 2008 07:11:07 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S934250AbYEBLKj (ORCPT ); Fri, 2 May 2008 07:10:39 -0400 Received: from wf-out-1314.google.com ([209.85.200.175]:16680 "EHLO wf-out-1314.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1765920AbYEBLKh (ORCPT ); Fri, 2 May 2008 07:10:37 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=QVNIbK3krpygsd6MLhUFqoMzvJJrKkjDCjsPokhUc7XpIc96gqT+76S3XjS8Clv9+LLu3ArF0HsTSPcBZP/7s0M3vFl8BvqplDcKlKN/NiJozMQAsjFrAnVuds/5dL/xO/qUUPHSodoyhWKM+Jb3e6C3c+Ra1jXECbmiPABvCCU= Message-ID: <82e4877d0805020410u78c6f03fr8e8e53d5a19f6846@mail.gmail.com> Date: Fri, 2 May 2008 07:10:37 -0400 From: "Parag Warudkar" To: "Peter Zijlstra" Subject: Re: Horrendous Audio Stutter - current git Cc: "Ingo Molnar" , LKML , "Frans Pop" , "Mike Galbraith" In-Reply-To: <1209717278.13978.136.camel@twins> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <82e4877d0805011714m35a47753q58cca706b7af6557@mail.gmail.com> <1209717278.13978.136.camel@twins> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 2, 2008 at 4:34 AM, Peter Zijlstra wrote: > On Thu, 2008-05-01 at 20:14 -0400, Parag Warudkar wrote: > > Parag, would you also test with !NEW_FAIR_SLEEPERS to see if that solves > your problem? > > The easiest way to disable it is (assumes you have debugfs mounted > at /debug): > > # echo NO_NEW_FAIR_SLEEPERS > /debug/sched_features Seems to make it stutter a little less - but still not usable. > > You can also disable NORMALIZED_SLEEPER that way (of course you would > first have to enable NEW_FAIR_SLEEPERS again): > > # echo NO_NORMALIZED_SLEEPER > /debug/sched_features > No significant difference from NO_NEW_FAIR_SLEEPERS that I can tell. > So by default we have both enabled; could you report if either > > NO_NEW_FAIR_SLEEPERS > > NEW_FAIR_SLEEPERS + NO_NORMALIZED_SLEEPERS > > works for you? I would say no - the audio still is unusable - slightly better with NO_NEW_FAIR_SLEEPERS, no difference with the other. But per Mike's suggestion if I disable CONFIG_GROUP_SCHED , CONFIG_FAIR_GROUP_SCHED and CONFIG_USER_SCHED, even with NEW_FAIR_SLEEPERS audio is good again, which does not change with NO_NEW_FAIR_SLEEPERS. (No skips for long time under -j8 - still skips a _very_ tiny bit - noticeable if I listen too carefully - but we can ignore that for the time being.) Mike - the GROUP_SCHED stuff is set to y in the Ubuntu kernel and I have no audio skips - may be a regression introduced after 2.6.24? But why is the GROUP_SCHED stuff default y if it so unusable? > > Also, could you apply this patch, and report the bonus_max value for > your music player under all three scenarios? > I see Frans already reported that and there was some conclusion - let me know if more data will help. Thanks! Parag