From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1422655AbXCWGwQ (ORCPT ); Fri, 23 Mar 2007 02:52:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1422652AbXCWGwM (ORCPT ); Fri, 23 Mar 2007 02:52:12 -0400 Received: from netops-testserver-4-out.sgi.com ([192.48.171.29]:33713 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S933820AbXCWGwF (ORCPT ); Fri, 23 Mar 2007 02:52:05 -0400 Date: Thu, 22 Mar 2007 23:52:05 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Andrew Morton cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [QUICKLIST 1/5] Quicklists for page table pages V4 In-Reply-To: <20070322223927.bb4caf43.akpm@linux-foundation.org> Message-ID: References: <20070323062843.19502.19827.sendpatchset@schroedinger.engr.sgi.com> <20070322223927.bb4caf43.akpm@linux-foundation.org> 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 On Thu, 22 Mar 2007, Andrew Morton wrote: > On Thu, 22 Mar 2007 23:28:41 -0700 (PDT) Christoph Lameter wrote: > > > 1. Proven code from the IA64 arch. > > > > The method used here has been fine tuned for years and > > is NUMA aware. It is based on the knowledge that accesses > > to page table pages are sparse in nature. Taking a page > > off the freelists instead of allocating a zeroed pages > > allows a reduction of number of cachelines touched > > in addition to getting rid of the slab overhead. So > > performance improves. > > By how much? About 40% on fork+exit. See http://marc.info/?l=linux-ia64&m=110942798406005&w=2