Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753811AbYJWOKW (ORCPT ); Thu, 23 Oct 2008 10:10:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751638AbYJWOKG (ORCPT ); Thu, 23 Oct 2008 10:10:06 -0400 Received: from nlpi025.sbcis.sbc.com ([207.115.36.54]:38254 "EHLO nlpi025.prodigy.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751055AbYJWOKF (ORCPT ); Thu, 23 Oct 2008 10:10:05 -0400 Date: Thu, 23 Oct 2008 07:09:24 -0700 (PDT) From: Christoph Lameter X-X-Sender: cl@quilx.com To: Pekka Enberg cc: Miklos Szeredi , nickpiggin@yahoo.com.au, hugh@veritas.com, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org Subject: Re: SLUB defrag pull request? In-Reply-To: <84144f020810230658o7c6b3651k2d671aab09aa71fb@mail.gmail.com> Message-ID: References: <1223883004.31587.15.camel@penberg-laptop> <84144f020810221348j536f0d84vca039ff32676e2cc@mail.gmail.com> <1224745831.25814.21.camel@penberg-laptop> <84144f020810230658o7c6b3651k2d671aab09aa71fb@mail.gmail.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed X-Spam-Score: -2.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1256 Lines: 27 On Thu, 23 Oct 2008, Pekka Enberg wrote: > On Thu, Oct 23, 2008 at 4:40 PM, Christoph Lameter > wrote: >> Solid? What is not solid? The SLUB design was made in part because of the >> defrag problems that were not easy to solve with SLAB. The ability to lock >> down a slab allows stabilizing objects. We discussed solutions to the >> fragmentation problem for years and did not get anywhere with SLAB. > > I'd assume he's talking about the Intel-reported regression that's yet > to be resolved. On that subject: Got a draft of a patch here that does freelist handling differently. Instead of building linked lists it uses free objects to build arrays of pointers to free objects. That improves cache cold free behavior since the object contents itself does not have to be touched on free. The problem looks like its freeing objects on a different processor that where it was used last. With the pointer array it is only necessary to touch the objects that contain the arrays. -- 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/