From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754638Ab1J0O3M (ORCPT ); Thu, 27 Oct 2011 10:29:12 -0400 Received: from gir.skynet.ie ([193.1.99.77]:53470 "EHLO gir.skynet.ie" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750879Ab1J0O3L (ORCPT ); Thu, 27 Oct 2011 10:29:11 -0400 Date: Thu, 27 Oct 2011 16:29:08 +0200 From: Mel Gorman To: Dimitri Sivanich Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , Christoph Lameter , David Rientjes , Andi Kleen Subject: Re: [PATCH] cache align vm_stat Message-ID: <20111027142858.GB6563@csn.ul.ie> References: <20111027085008.GA6563@csn.ul.ie> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20111027085008.GA6563@csn.ul.ie> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 27, 2011 at 10:50:25AM +0200, Mel Gorman wrote: > On Mon, Oct 24, 2011 at 11:10:35AM -0500, Dimitri Sivanich wrote: > > Avoid false sharing of the vm_stat array. > > > > This was found to adversely affect tmpfs I/O performance. > > > > I think this fix is overly simplistic. In a lesson on why I should not even try reviewing while attending conferences, I totally misread what the patch is doing. It's aligning the array to avoid false sharing with other global data, not aligning each element. This is reasonable. Acked-by: Mel Gorman