From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752900AbXC1VAq (ORCPT ); Wed, 28 Mar 2007 17:00:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752902AbXC1VAq (ORCPT ); Wed, 28 Mar 2007 17:00:46 -0400 Received: from netops-testserver-4-out.sgi.com ([192.48.171.29]:47284 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752886AbXC1VAp (ORCPT ); Wed, 28 Mar 2007 17:00:45 -0400 Date: Wed, 28 Mar 2007 14:00:44 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: William Lee Irwin III cc: linux-kernel@vger.kernel.org, akpm@linux-foundation.org Subject: Re: [RFC] i386: Remove page sized slabs for pgds and pmds In-Reply-To: <20070328205055.GX8915@holomorphy.com> Message-ID: References: <20070328205055.GX8915@holomorphy.com> 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 Wed, 28 Mar 2007, William Lee Irwin III wrote: > Getting the relevant results without tremendous amounts of noise from > other kernel activity needs something like lmbench's fault and fork() > microbenchmarks. Also, /proc/profile and/or oprofile results would be > useful here to get useful notions of what's happening performancewise, > in particular oprofile with L2 cache miss performance counters. The machine had a minimal debian root and it was run on a serial console. > it's in the noise. PMD and PTE caching are only pertinent to fork() > anyway, so the vast majority of your workload is unaffected, and it's I'd be interested to see some numbers here. I still believe the situation to be better on IA64 and other platforms due to the larger page sizes containing many more cachelines which should make the effect bigger.