Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760077AbZFKTCb (ORCPT ); Thu, 11 Jun 2009 15:02:31 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758834AbZFKTBs (ORCPT ); Thu, 11 Jun 2009 15:01:48 -0400 Received: from smtp3.ultrahosting.com ([74.213.175.254]:37499 "EHLO smtp.ultrahosting.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1759520AbZFKTBq (ORCPT ); Thu, 11 Jun 2009 15:01:46 -0400 Date: Thu, 11 Jun 2009 14:26:02 -0400 (EDT) From: Christoph Lameter X-X-Sender: cl@gentwo.org To: Mel Gorman cc: Pekka Enberg , linux-kernel@vger.kernel.org, Larry.Finger@lwfinger.net Subject: Re: [PATCH 2/2] SLUB: Disable debugging if it increases the minimum page order In-Reply-To: <20090611180422.GJ7302@csn.ul.ie> Message-ID: References: <1244728824.17483.51.camel@penberg-laptop> <1244733119.17483.56.camel@penberg-laptop> <1244734086.17483.59.camel@penberg-laptop> <20090611180422.GJ7302@csn.ul.ie> User-Agent: Alpine 1.10 (DEB 962 2008-03-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1055 Lines: 22 On Thu, 11 Jun 2009, Mel Gorman wrote: > "With SLUB_DEBUG, enable debug on all caches unless the increased meta-data > would force the minimum order up on order due to object sizes being near or > equal the PAGE_SIZE. If SLUB_DEBUG must be enabled, specify slub_debug=A for > 'All caches enable debug regardless'" Hmmm... No SLUB_DEBUG just compiles the code in for debugging. Does not enable anything. But we could make SLUB_DEBUG_ON enable debugging except on those slabs where the order increases (for which it does a printk saying that the debugging was disabled) and then have a slub_debug=A option that overrides the order check. Generally if you know that you have memory corruption you would want to boot with slub_debug=A. If you just want continuous checks then SLUB_DEBUG_ON would do the trick. -- 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/