Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756677AbYGRJ52 (ORCPT ); Fri, 18 Jul 2008 05:57:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754418AbYGRJ5V (ORCPT ); Fri, 18 Jul 2008 05:57:21 -0400 Received: from anchor-post-35.mail.demon.net ([194.217.242.85]:1211 "EHLO anchor-post-35.mail.demon.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753698AbYGRJ5V (ORCPT ); Fri, 18 Jul 2008 05:57:21 -0400 Subject: Re: [PATCH][RFC] slub: increasing order reduces memory usage of some key caches From: Richard Kennedy To: Christoph Lameter Cc: penberg@cs.helsinki.fi, mpm@selenic.com, linux-mm , lkml , Mel Gorman In-Reply-To: <487DFFBE.5050407@linux-foundation.org> References: <1216211371.3122.46.camel@castor.localdomain> <487DF5D4.9070101@linux-foundation.org> <1216216730.3122.60.camel@castor.localdomain> <487DFFBE.5050407@linux-foundation.org> Content-Type: text/plain Date: Fri, 18 Jul 2008 10:57:05 +0100 Message-Id: <1216375025.3082.7.camel@castor.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.12.3 (2.12.3-5.fc8) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3502 Lines: 83 On Wed, 2008-07-16 at 09:03 -0500, Christoph Lameter wrote: > Richard Kennedy wrote: > > > before > > dentry 82136 82137 208 19 1 : tunables 0 0 0 : slabdata 4323 4323 0 > > after > > dentry 79482 79482 208 39 2 : tunables 0 0 0 : slabdata 2038 2038 0 > > 19 objects with an order 1 alloc and 208 byte size? Urgh. 8192/208 = 39 and not 19. > > Kmemcheck or something else active? We seem to be loosing 50% of our memory. > > Pekka: Is the slabinfo emulation somehow broken? > > I'd really like to see the output of slabinfo dentry. > here's that slabinfo for dentry on 2.6.26 after booting & starting X Slabcache: dentry Aliases: 0 Order : 0 Objects: 22553 ** Reclaim accounting active Sizes (bytes) Slabs Debug Memory ------------------------------------------------------------------------ Object : 208 Total : 1188 Sanity Checks : Off Total: 4866048 SlabObj: 208 Full : 1186 Redzoning : Off Used : 4691024 SlabSiz: 4096 Partial: 0 Poisoning : Off Loss : 175024 Loss : 0 CpuSlab: 2 Tracking : Off Lalig: 0 Align : 8 Objects: 19 Tracing : Off Lpadd: 171072 and after a make kernel & a small delay dentry: No NUMA information available. Slabcache: radix_tree_node Aliases: 0 Order : 1 Objects: 33564 ** Reclaim accounting active Sizes (bytes) Slabs Debug Memory ------------------------------------------------------------------------ Object : 552 Total : 2399 Sanity Checks : Off Total: 19652608 SlabObj: 560 Full : 2391 Redzoning : Off Used : 18527328 SlabSiz: 8192 Partial: 6 Poisoning : Off Loss : 1125280 Loss : 8 CpuSlab: 2 Tracking : Off Lalig: 268512 Align : 0 Objects: 14 Tracing : Off Lpadd: 844448 ************* on 2.6.26 + my patch Slabcache: dentry Aliases: 0 Order : 1 Objects: 22581 ** Reclaim accounting active Sizes (bytes) Slabs Debug Memory ------------------------------------------------------------------------ Object : 208 Total : 579 Sanity Checks : Off Total: 4743168 SlabObj: 208 Full : 577 Redzoning : Off Used : 4696848 SlabSiz: 8192 Partial: 0 Poisoning : Off Loss : 46320 Loss : 0 CpuSlab: 2 Tracking : Off Lalig: 0 Align : 8 Objects: 39 Tracing : Off Lpadd: 46320 after the make Slabcache: dentry Aliases: 0 Order : 1 Objects: 80168 ** Reclaim accounting active Sizes (bytes) Slabs Debug Memory ------------------------------------------------------------------------ Object : 208 Total : 2056 Sanity Checks : Off Total: 16842752 SlabObj: 208 Full : 2043 Redzoning : Off Used : 16674944 SlabSiz: 8192 Partial: 11 Poisoning : Off Loss : 167808 Loss : 0 CpuSlab: 2 Tracking : Off Lalig: 0 Align : 8 Objects: 39 Tracing : Off Lpadd: 164480 Richard -- 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/