From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx170.postini.com [74.125.245.170]) by kanga.kvack.org (Postfix) with SMTP id 46F346B002C for ; Mon, 5 Mar 2012 05:33:56 -0500 (EST) Received: by lagz14 with SMTP id z14so6264244lag.14 for ; Mon, 05 Mar 2012 02:33:54 -0800 (PST) Date: Mon, 5 Mar 2012 12:33:49 +0200 (EET) From: Pekka Enberg Subject: Re: [PATCH] mm: SLAB Out-of-memory diagnostics In-Reply-To: <20120302143323.GB1868@t510.redhat.com> Message-ID: References: <20120229032715.GA23758@t510.redhat.com> <20120302143323.GB1868@t510.redhat.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Rafael Aquini Cc: David Rientjes , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Randy Dunlap , Christoph Lameter , Matt Mackall , Rik van Riel , Josef Bacik On Fri, 2 Mar 2012, Rafael Aquini wrote: > On Wed, Feb 29, 2012 at 05:26:07PM -0800, David Rientjes wrote: > > On Wed, 29 Feb 2012, Rafael Aquini wrote: > > > > > Following the example at mm/slub.c, add out-of-memory diagnostics to the SLAB > > > allocator to help on debugging OOM conditions. This patch also adds a new > > > sysctl, 'oom_dump_slabs_forced', that overrides the effect of __GFP_NOWARN page > > > allocation flag and forces the kernel to report every slab allocation failure. > > > > > > An example print out looks like this: > > > > > > > > > SLAB: Unable to allocate memory on node 0 (gfp=0x11200) > > > cache: bio-0, object size: 192, order: 0 > > > node0: slabs: 3/3, objs: 60/60, free: 0 > > > > > > Signed-off-by: Rafael Aquini > > > > I like it, except for the addition of the sysctl. __GFP_NOWARN is used > > for a reason, usually because whatever is allocating memory can gracefully > > handle a failure and should not be emitted to the kernel log under any > > circumstances. > > Ok, I'll drop the sysctl part then. Pekka? Yes, please. -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org