From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx206.postini.com [74.125.245.206]) by kanga.kvack.org (Postfix) with SMTP id A9A1A6B002C for ; Wed, 29 Feb 2012 20:26:09 -0500 (EST) Received: by pbbro12 with SMTP id ro12so275739pbb.14 for ; Wed, 29 Feb 2012 17:26:08 -0800 (PST) Date: Wed, 29 Feb 2012 17:26:07 -0800 (PST) From: David Rientjes Subject: Re: [PATCH] mm: SLAB Out-of-memory diagnostics In-Reply-To: <20120229032715.GA23758@t510.redhat.com> Message-ID: References: <20120229032715.GA23758@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: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Randy Dunlap , Christoph Lameter , Pekka Enberg , Matt Mackall , Rik van Riel , Josef Bacik 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. -- 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