Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261621AbVCRPBD (ORCPT ); Fri, 18 Mar 2005 10:01:03 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261623AbVCRPBC (ORCPT ); Fri, 18 Mar 2005 10:01:02 -0500 Received: from omx1-ext.sgi.com ([192.48.179.11]:53485 "EHLO omx1.americas.sgi.com") by vger.kernel.org with ESMTP id S261621AbVCRPA4 (ORCPT ); Fri, 18 Mar 2005 10:00:56 -0500 Date: Fri, 18 Mar 2005 07:00:06 -0800 (PST) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Denis Vlasenko cc: Dave Hansen , Andi Kleen , Andrew Morton , Linux Kernel Mailing List , Mel Gorman , linux-ia64@vger.kernel.org, Jens.Maurer@gmx.net Subject: Re: [PATCH] add a clear_pages function to clear pages of higher order In-Reply-To: <200503181154.37414.vda@port.imtp.ilyichevsk.odessa.ua> Message-ID: References: <200503111008.12134.vda@port.imtp.ilyichevsk.odessa.ua> <200503181154.37414.vda@port.imtp.ilyichevsk.odessa.ua> 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: 1098 Lines: 22 On Fri, 18 Mar 2005, Denis Vlasenko wrote: > NT stores are not about 5% increase. 200%-300%. Provided you are ok with > the fact that zeroed page ends up evicted from cache. Luckily, this is exactly > what you want with prezeroing. These are pretty significant results. Maybe its best to use non-temporal stores in general for clearing pages? I checked and Itanium has always used non-temporal stores. So there will be no benefit for us from this approach (we have 16k and 64k page sizes which may make the situation a bit different). Try to update the i386 architectures to do the same? Or for prezeroing, you could register a zeroing driver that would use the non-temporal stores with V8 of the prezeroing patches. In any case the clear_pages patch is not useful the way it was intended for us and I am have dropped this from the prezeroing patch. - 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/