Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751245AbXBNUsG (ORCPT ); Wed, 14 Feb 2007 15:48:06 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751243AbXBNUrp (ORCPT ); Wed, 14 Feb 2007 15:47:45 -0500 Received: from mx1.redhat.com ([66.187.233.31]:47616 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751239AbXBNUrn (ORCPT ); Wed, 14 Feb 2007 15:47:43 -0500 Date: Wed, 14 Feb 2007 15:47:31 -0500 From: Dave Jones To: Marcelo Tosatti Cc: Jordan Crouse , Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: [PATCH] use movntq version of fast_clear_page/fast_copy_page on Geode Message-ID: <20070214204731.GA4551@redhat.com> Mail-Followup-To: Dave Jones , Marcelo Tosatti , Jordan Crouse , Andrew Morton , linux-kernel@vger.kernel.org References: <20070214190839.GA4864@dmt.lan> <20070214195546.GA2005@redhat.com> <20070214201736.GA5794@dmt.lan> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070214201736.GA5794@dmt.lan> User-Agent: Mutt/1.4.2.2i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1385 Lines: 33 On Wed, Feb 14, 2007 at 06:17:36PM -0200, Marcelo Tosatti wrote: > On Wed, Feb 14, 2007 at 02:55:46PM -0500, Dave Jones wrote: > > On Wed, Feb 14, 2007 at 05:08:39PM -0200, Marcelo Tosatti wrote: > > > > > > movntq instruction is supported by Geode CPU's, so use > > > fast_clear_page/fast_copy_page versions that have it. > > > > it's supported, but is it a win ? > > The same was also true of the VIA C3/C7's, but due to > > poor memory bandwidth, it turned out to be slower in most cases. > > Do you have the numbers for VIA C3/C7 around? I don't, and my 3dnow capable C3s are unplugged right now. The newer generation (including the C7) have SSE/SSE2 instead, which seems to be faster. (Using a different benchmark app that uses SSE) clear_page function 'normal clear_page()' took 9425 cycles per page (620.3 MB/s) clear_page function 'new clear_page() ' took 3840 cycles per page (1522.7 MB/s) copy_page function 'normal copy_page()' took 11453 cycles per page (510.5 MB/s) copy_page function 'new copy_page() ' took 5024 cycles per page (1163.7 MB/s) Dave -- http://www.codemonkey.org.uk - 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/