Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932852Ab3JOMEN (ORCPT ); Tue, 15 Oct 2013 08:04:13 -0400 Received: from mail-ea0-f179.google.com ([209.85.215.179]:64846 "EHLO mail-ea0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758143Ab3JOMEK (ORCPT ); Tue, 15 Oct 2013 08:04:10 -0400 Date: Tue, 15 Oct 2013 14:04:04 +0200 From: Ingo Molnar To: Borislav Petkov Cc: Joe Perches , Eric Dumazet , Neil Horman , linux-kernel@vger.kernel.org, sebastien.dugue@bull.net, Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org Subject: Re: [PATCH] x86: Run checksumming in parallel accross multiple alu's Message-ID: <20131015120404.GA2402@gmail.com> References: <1381510298-20572-1-git-send-email-nhorman@tuxdriver.com> <20131012172124.GA18241@gmail.com> <20131014202854.GH26880@hmsreliant.think-freely.org> <1381785560.2045.11.camel@edumazet-glaptop.roam.corp.google.com> <1381789127.2045.22.camel@edumazet-glaptop.roam.corp.google.com> <1381790278.16896.2.camel@joe-AO722> <1381790686.2045.24.camel@edumazet-glaptop.roam.corp.google.com> <1381790982.16896.7.camel@joe-AO722> <20131015074123.GB25493@gmail.com> <20131015105159.GA8682@pd.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20131015105159.GA8682@pd.tnic> 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 Content-Length: 782 Lines: 23 * Borislav Petkov wrote: > On Tue, Oct 15, 2013 at 09:41:23AM +0200, Ingo Molnar wrote: > > Most processors have hundreds of cachelines even in their L1 cache. > > Thousands in the L2 cache, up to hundreds of thousands. > > Also, I have this hazy memory of prefetch hints being harmful in some > situations: https://lwn.net/Articles/444344/ Yes, for things like random list walks they tend to be harmful - the hardware is smarter. For something like a controlled packet stream they might be helpful. Thanks, Ingo -- 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/