Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751952AbXEXQtQ (ORCPT ); Thu, 24 May 2007 12:49:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750786AbXEXQtA (ORCPT ); Thu, 24 May 2007 12:49:00 -0400 Received: from mga09.intel.com ([134.134.136.24]:40048 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750721AbXEXQs7 (ORCPT ); Thu, 24 May 2007 12:48:59 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.14,574,1170662400"; d="scan'208";a="90162834" Date: Thu, 24 May 2007 09:45:38 -0700 From: "Siddha, Suresh B" To: Peter Williams Cc: Ingo Molnar , colpatch@us.ibm.com, "Siddha, Suresh B" , Nick Piggin , Con Kolivas , Christoph Lameter , Dmitry Adamushko , Linux Kernel Subject: Re: [patch] CFS scheduler, -v12 Message-ID: <20070524164538.GA13301@linux-os.sc.intel.com> References: <464A6698.3080400@bigpond.net.au> <20070516063625.GA9058@elte.hu> <464CE8FD.4070205@bigpond.net.au> <20070518071325.GB28702@elte.hu> <464DA61A.4040406@bigpond.net.au> <46523081.6050007@bigpond.net.au> <465275EF.8060905@bigpond.net.au> <4652DC03.60801@bigpond.net.au> <4655423E.6000202@bigpond.net.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4655423E.6000202@bigpond.net.au> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1606 Lines: 35 On Thu, May 24, 2007 at 12:43:58AM -0700, Peter Williams wrote: >Peter Williams wrote: >> The relevant code, find_busiest_group() and find_busiest_queue(), has a >> lot of code that is ifdefed by CONFIG_SCHED_MC and CONFIG_SCHED_SMT and, >> as these macros were defined in the kernels I was testing with, I built >> a kernel with these macros undefined and reran my tests. The >> problems/anomalies were not present in 10 consecutive tests on this new >> kernel. Even better on the few occasions that a 3/1 split did occur it >> was quickly corrected to 2/2 and top was reporting approx 49% of CPU for >> all spinners throughout each of the ten tests. >> >> So all that is required now is an analysis of the code inside the ifdefs >> to see why it is causing a problem. > > >Further testing indicates that CONFIG_SCHED_MC is not implicated and >it's CONFIG_SCHED_SMT that's causing the problem. This rules out the >code in find_busiest_group() as it is common to both macros. > >I think this makes the scheduling domain parameter values the most >likely cause of the problem. I'm not very familiar with this code so >I've added those who've modified this code in the last year or >so to the >address of this e-mail. What platform is this? I remember you mentioned its a 2 cpu box. Is it dual core or dual package or one with HT? thanks, suresh - 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/