Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934720Ab0GOUip (ORCPT ); Thu, 15 Jul 2010 16:38:45 -0400 Received: from mail-bw0-f46.google.com ([209.85.214.46]:43478 "EHLO mail-bw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934691Ab0GOUio convert rfc822-to-8bit (ORCPT ); Thu, 15 Jul 2010 16:38:44 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=references:in-reply-to:mime-version:content-transfer-encoding :content-type:message-id:cc:x-mailer:from:subject:date:to; b=IPBANNCzVSsyYLbEhI6aPqa4pPRm6v7/e08C13E2GSvaE/I6H4Av1PisowvCGh0elF IJ3byVzCLGXxjzCW6garQj6WAAOGsK9AB+ACVOn2Jru8ENklQfak5w5v03uk6yxlM7qC sx8ZPwSm4OTBafc99lK2GPs7KuGHOSz3Cfqkw= References: <1279100846.8592.53.camel@e102109-lin.cambridge.arm.com> <4C3D89AC.4040303@cs.helsinki.fi> <1279205891.6664.46.camel@e102109-lin.cambridge.arm.com> <4C3F2F52.2050101@cs.helsinki.fi> <20100715162805.GA10240@brouette> <20100715191638.GA3694@brouette> <20100715200012.GA4175@brouette> In-Reply-To: <20100715200012.GA4175@brouette> Mime-Version: 1.0 (iPhone Mail 8A293) Content-Transfer-Encoding: 8BIT Content-Type: text/plain; charset=us-ascii Message-Id: Cc: Pekka Enberg , Catalin Marinas , "linux-kernel@vger.kernel.org" , Andrew Morton , "x86@kernel.org" , "mingo@elte.hu" , "yinghai@kernel.org" , Peter Zijlstra X-Mailer: iPhone Mail (8A293) From: Zeno Davatz Subject: Re: kmemleak, cpu usage jump out of nowhere Date: Thu, 15 Jul 2010 22:38:45 +0200 To: Damien Wyart Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1954 Lines: 36 Am 15.07.2010 um 22:00 schrieb Damien Wyart : >>> For now, I can't reproduce the problem with CONFIG_NO_BOOTMEM disabled ; >>> with the option and rc5 the problem was happening quite quickly after >>> boot and normal use of the machine. So it seems I can confirme what Zeno >>> has seen and I hope this will give a hint to debug the problem. I guess >>> this has not been reported that much because many testers might not have >>> enabled CONFIG_NO_BOOTMEM... Maybe the scheduler folks could test their >>> benchmark with a kernel having this option enabled? > > * Pekka Enberg [2010-07-15 22:50]: >> To be honest, the bug is bit odd. It's related to boot-time memory >> allocator changes but yet it seems to manifest itself as a scheduling >> problem. So if you have some spare time and want to speed up the >> debugging process, please test v2.6.34 and v2.6.35-rc1 with >> CONFIG_NO_BOOTMEM and if former is good and latter is bad, try to see >> if you can identify the offending commit with "git bisect." > > Not sure I will have enough time in the coming days (doing that remotely > is fishy since ssh access is almost stuck when the problem occurs); if > Zeno can and would like to do it, maybe this could be done faster. > > As the scheduler is now very well instrumented (many debugging features > are available), reproducing the bug on a test platform (it happens quite > quickly for me) might also give some hints. So testers, if you have > time, please test 2.6.35-rc5 with CONFIG_NO_BOOTMEM on a Core i7 and see > if you can reproduce the problem! Will try to do so. Can you point me to the git bisect howto with the versions you want. Best Zeno-- 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/