Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S275324AbTHMSxS (ORCPT ); Wed, 13 Aug 2003 14:53:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S275351AbTHMSxR (ORCPT ); Wed, 13 Aug 2003 14:53:17 -0400 Received: from mail.suse.de ([213.95.15.193]:8466 "EHLO Cantor.suse.de") by vger.kernel.org with ESMTP id S275324AbTHMSxO (ORCPT ); Wed, 13 Aug 2003 14:53:14 -0400 Date: Wed, 13 Aug 2003 20:53:12 +0200 From: Andi Kleen To: Alan Cox Cc: Andi Kleen , Linux Kernel Mailing List Subject: Re: 2.6.0-test3-mm1: scheduling while atomic (ext3?) Message-ID: <20030813185312.GI21081@wotan.suse.de> References: <20030813042544.5064b3f4.akpm@osdl.org.suse.lists.linux.kernel> <1060774803.8008.24.camel@localhost.localdomain.suse.lists.linux.kernel> <1060778924.8008.39.camel@localhost.localdomain> <20030813131457.GD32290@wotan.suse.de> <1060783794.8008.62.camel@dhcp23.swansea.linux.org.uk> <20030813142055.GC9179@wotan.suse.de> <1060788009.8957.5.camel@dhcp23.swansea.linux.org.uk> <20030813153235.GB21081@wotan.suse.de> <1060800263.9130.29.camel@dhcp23.swansea.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1060800263.9130.29.camel@dhcp23.swansea.linux.org.uk> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1145 Lines: 28 On Wed, Aug 13, 2003 at 07:44:24PM +0100, Alan Cox wrote: > On Mer, 2003-08-13 at 16:32, Andi Kleen wrote: > > The AMD slides assume all very big data sets ;-) > > > > I would recommend to remove it. > > I'll do some timings when I get a moment - the prefetching mmx copy Microbenchmarks are useless for this. You have to bench the users too, otherwise you don't recognize the additional cache misses. > was a win (and faster than the others for small data as well as large > on the K7-550 (really a K7 not "Athlon" 8)) way back when. Possible. In my experience the best copy functions vary widly between different steppings. Just optimizing for a single one is probably not a good idea, especially not for an very old one (except when you add dynamic patches for the different steppings, but then it quickly gets ugly with too many variants) When in doubt use the more simple function. -Andi - 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/