From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with ESMTP id 245ED6B015F for ; Wed, 26 Aug 2009 07:08:06 -0400 (EDT) Date: Wed, 26 Aug 2009 12:08:09 +0100 From: Mel Gorman Subject: Re: VM issue causing high CPU loads Message-ID: <20090826110809.GG10955@csn.ul.ie> References: <4A92A25A.4050608@yohan.staff.proxad.net> <20090824162155.ce323f08.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20090824162155.ce323f08.akpm@linux-foundation.org> Sender: owner-linux-mm@kvack.org To: Andrew Morton Cc: Yohan , linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On Mon, Aug 24, 2009 at 04:21:55PM -0700, Andrew Morton wrote: > On Mon, 24 Aug 2009 16:23:22 +0200 > Yohan wrote: > > > Hi, > > > > Is someone have an idea for that : > > > > http://bugzilla.kernel.org/show_bug.cgi?id=14024 > > > > Please generate a kernel profile to work out where all the CPU tie is > being spent. Documentation/basic_profiling.txt is a starting point. > In the absense of a profile, here is a total stab in the dark. Is this a NUMA machine? If so, is /proc/sys/vm/zone_reclaim_mode set to 1 and does setting it to 0 help? This is based on a relatively recent bug where malloc() could stall for long times with large amounts of CPU usage due to useless scanning in page reclaim. -- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org