Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757346AbXJAVqY (ORCPT ); Mon, 1 Oct 2007 17:46:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753991AbXJAVqP (ORCPT ); Mon, 1 Oct 2007 17:46:15 -0400 Received: from smtp2.linux-foundation.org ([207.189.120.14]:41694 "EHLO smtp2.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753811AbXJAVqO (ORCPT ); Mon, 1 Oct 2007 17:46:14 -0400 Date: Mon, 1 Oct 2007 14:45:43 -0700 From: Andrew Morton To: Christoph Lameter Cc: a.p.zijlstra@chello.nl, nickpiggin@yahoo.com.au, hch@lst.de, mel@skynet.ie, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, dgc@sgi.com, jens.axboe@oracle.com Subject: Re: [15/17] SLUB: Support virtual fallback via SLAB_VFALLBACK Message-Id: <20071001144543.4cfa1e44.akpm@linux-foundation.org> In-Reply-To: References: <20070919033605.785839297@sgi.com> <20070919033643.763818012@sgi.com> <200709280742.38262.nickpiggin@yahoo.com.au> <1191002119.18147.80.camel@lappy> <1191003950.18147.85.camel@lappy> <20070929011311.8b51dedb.akpm@linux-foundation.org> <1191055632.18147.101.camel@lappy> <20070929020049.f73f4aea.akpm@linux-foundation.org> <20071001143047.238dfe49.akpm@linux-foundation.org> X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.20; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1384 Lines: 37 On Mon, 1 Oct 2007 14:38:55 -0700 (PDT) Christoph Lameter wrote: > On Mon, 1 Oct 2007, Andrew Morton wrote: > > > Do slab and slub use the same underlying page size for each slab? > > SLAB cannot pack objects as dense as SLUB and they have different > algorithm to make the choice of order. Thus the number of objects per slab > may vary between SLAB and SLUB and therefore also the choice of order to > store these objects. > > > Single data point: the CONFIG_SLAB boxes which I have access to here are > > using order-0 for radix_tree_node, so they won't be failing in the way in > > which Peter's machine is. > > Upstream SLUB uses order 0 allocations for the radix tree. OK, that's a relief. > MM varies > because the use of higher order allocs is more loose if the mobility > algorithms are found to be active: > > 2.6.23-rc8: > > Name Objects Objsize Space Slabs/Part/Cpu O/S O %Fr %Ef Flg\ > radix_tree_node 14281 552 9.9M 2432/948/1 7 0 38 79 Ah. So the already-dropped slub-exploit-page-mobility-to-increase-allocation-order.patch was the culprit? - 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/