Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S970639AbXFHSQX (ORCPT ); Fri, 8 Jun 2007 14:16:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1031119AbXFHSQP (ORCPT ); Fri, 8 Jun 2007 14:16:15 -0400 Received: from netops-testserver-3-out.sgi.com ([192.48.171.28]:40011 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1031116AbXFHSQO (ORCPT ); Fri, 8 Jun 2007 14:16:14 -0400 Date: Fri, 8 Jun 2007 11:16:13 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Michal Piotrowski cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, dgc@sgi.com, Mel Gorman Subject: Re: [patch 00/12] Slab defragmentation V3 In-Reply-To: <466999A2.8020608@googlemail.com> Message-ID: References: <20070607215529.147027769@sgi.com> <466999A2.8020608@googlemail.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1252 Lines: 40 On Fri, 8 Jun 2007, Michal Piotrowski wrote: > bash shared mapping + your script in a loop > while true; do sudo ./run.sh; done > res3.txt Hmmmm... Seems to be triggered from the reclaim path kmem_cache_defrag rather than the manual triggered one from the script. Taking the slub_lock on the reclaim path is an issue it seems. Maybe we need to do a trylock in kmem_cache_defrag to defuse the situation? This is after all an optimization so we can bug out. Does this fix it? --- mm/slub.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) Index: slub/mm/slub.c =================================================================== --- slub.orig/mm/slub.c 2007-06-08 11:12:40.000000000 -0700 +++ slub/mm/slub.c 2007-06-08 11:14:34.000000000 -0700 @@ -2738,7 +2738,9 @@ int kmem_cache_defrag(int percent, int n unsigned long pages = 0; void *scratch; - down_read(&slub_lock); + if (!down_read_trylock(&slub_lock)) + return 0; + list_for_each_entry(s, &slab_caches, list) { /* - 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/