Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761293AbXEURGx (ORCPT ); Mon, 21 May 2007 13:06:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762133AbXEURGm (ORCPT ); Mon, 21 May 2007 13:06:42 -0400 Received: from netops-testserver-4-out.sgi.com ([192.48.171.29]:36590 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1761957AbXEURGk (ORCPT ); Mon, 21 May 2007 13:06:40 -0400 Date: Mon, 21 May 2007 10:06:39 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Nick Piggin cc: William Lee Irwin III , Linux Kernel Mailing List , Linux Memory Management List , linux-arch@vger.kernel.org Subject: Re: [rfc] increase struct page size?! In-Reply-To: <20070520092552.GA7318@wotan.suse.de> Message-ID: References: <20070518040854.GA15654@wotan.suse.de> <20070519012530.GB15569@wotan.suse.de> <20070519181501.GC19966@holomorphy.com> <20070520052229.GA9372@wotan.suse.de> <20070520084647.GF19966@holomorphy.com> <20070520092552.GA7318@wotan.suse.de> 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 Content-Length: 788 Lines: 18 On Sun, 20 May 2007, Nick Piggin wrote: > I _am_ considering the average case, and I consider the aligned structure > is likely to win on average :) I just don't have numbers for it yet. I'd be glad too if you could get some numbers. I did some benchmarking a few weeks ago on x86_64 and I found only a very minimal performance drop if the calculation was simplified. Note also that a smaller structure means that more page structs can be covered by a certain amount of cachelines. Doing the alignment may cause more cacheline misses. - 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/