Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753902Ab0DONdX (ORCPT ); Thu, 15 Apr 2010 09:33:23 -0400 Received: from casper.infradead.org ([85.118.1.10]:40100 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753862Ab0DONdW (ORCPT ); Thu, 15 Apr 2010 09:33:22 -0400 Subject: Re: VM performance issue in KVM guests. From: Peter Zijlstra To: Avi Kivity Cc: Srivatsa Vaddagiri , "Zhang, Xiantao" , "kvm@vger.kernel.org" , Marcelo Tosatti , "Yang, Xiaowei" , "Dong, Eddie" , "Li, Xin" , Ingo Molnar , Mike Galbraith , Linux Kernel Mailing List , vatsa@linux.vnet.ibm.com In-Reply-To: <4BC6CBE3.8020207@redhat.com> References: <4BC0D125.9050108@redhat.com> <4BC2C07B.4040607@redhat.com> <4BC6CBE3.8020207@redhat.com> Content-Type: text/plain; charset="UTF-8" Date: Thu, 15 Apr 2010 15:33:18 +0200 Message-ID: <1271338398.1674.13.camel@laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 636 Lines: 15 On Thu, 2010-04-15 at 11:18 +0300, Avi Kivity wrote: > > Certainly that has even greater potential for Linux guests. Note that > we spin on mutexes now, so we need to prevent preemption while the lock > owner is running. either that, or disable spinning on (para) virt kernels. Para virt kernels could possibly extend the thing by also checking to see if the owner's vcpu is running. -- 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/