From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755435AbYGIM31 (ORCPT ); Wed, 9 Jul 2008 08:29:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751961AbYGIM3T (ORCPT ); Wed, 9 Jul 2008 08:29:19 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:39926 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751834AbYGIM3T (ORCPT ); Wed, 9 Jul 2008 08:29:19 -0400 Date: Wed, 9 Jul 2008 14:28:52 +0200 From: Ingo Molnar To: Jeremy Fitzhardinge Cc: Nick Piggin , LKML , Jens Axboe , Peter Zijlstra , Christoph Lameter , Petr Tesarik , Virtualization , Xen devel , Thomas Friebel , Avi Kivity Subject: Re: [PATCH RFC 0/4] Paravirtual spinlocks Message-ID: <20080709122852.GA30579@elte.hu> References: <20080707190749.299430659@goop.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080707190749.299430659@goop.org> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Jeremy Fitzhardinge wrote: > My experiments show that using a Xen-specific lock helps guest > performance a bit (reduction in elapsed and system time in a kernbench > run), but most significantly, reduces overall physical CPU consumption > by 10%, and so increases overall system scalability. that's rather impressive and looks nice, considering the fairly low impact. as there were no fundamental objections in this thread i've created a tip/x86/paravirt-spinlocks topic branch for these patches and started testing them. i based the topic branch on tip/xen-64bit, so you should be able to get the latest code by doing: git-merge tip/x86/paravirt-spinlocks on tip/master. Ingo From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ingo Molnar Subject: Re: [PATCH RFC 0/4] Paravirtual spinlocks Date: Wed, 9 Jul 2008 14:28:52 +0200 Message-ID: <20080709122852.GA30579@elte.hu> References: <20080707190749.299430659@goop.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20080707190749.299430659@goop.org> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Jeremy Fitzhardinge Cc: Jens Axboe , Nick Piggin , Xen devel , Peter Zijlstra , Christoph Lameter , Petr Tesarik , LKML , Avi Kivity , Virtualization , Thomas Friebel List-Id: xen-devel@lists.xenproject.org * Jeremy Fitzhardinge wrote: > My experiments show that using a Xen-specific lock helps guest > performance a bit (reduction in elapsed and system time in a kernbench > run), but most significantly, reduces overall physical CPU consumption > by 10%, and so increases overall system scalability. that's rather impressive and looks nice, considering the fairly low impact. as there were no fundamental objections in this thread i've created a tip/x86/paravirt-spinlocks topic branch for these patches and started testing them. i based the topic branch on tip/xen-64bit, so you should be able to get the latest code by doing: git-merge tip/x86/paravirt-spinlocks on tip/master. Ingo