From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH v3 0/6] Optimize vcpu->requests processing Date: Mon, 24 Sep 2012 12:52:08 +0200 Message-ID: <50603B58.5040703@redhat.com> References: <1341853545-3023-1-git-send-email-avi@redhat.com> <505FF5E3.3070101@linux.vnet.ibm.com> <50602C80.1090102@redhat.com> <506033C7.5000903@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Marcelo Tosatti , kvm@vger.kernel.org To: Xiao Guangrong Return-path: Received: from mx1.redhat.com ([209.132.183.28]:57375 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753909Ab2IXKwQ (ORCPT ); Mon, 24 Sep 2012 06:52:16 -0400 In-Reply-To: <506033C7.5000903@linux.vnet.ibm.com> Sender: kvm-owner@vger.kernel.org List-ID: On 09/24/2012 12:19 PM, Xiao Guangrong wrote: > On 09/24/2012 05:48 PM, Avi Kivity wrote: >> On 09/24/2012 07:55 AM, Xiao Guangrong wrote: >>> On 07/10/2012 01:05 AM, Avi Kivity wrote: >>>> Currently, any time a request bit is set (not too uncommon) we check all of them. >>>> This patchset optimizes the process slightly by skipping over unset bits using >>>> for_each_set_bit(). >>>> >>> >>> I also notice that kvm_check_request costs lots of cpu time. What is the status >>> of this patchset? >>> >> >> I had problems getting rid of KVM_REQ_PENDING_TIMER. I'll try again. >> >> In what workloads did you see kvm_check_request()? >> > > Run kernbench on guest, and use perf to sample, this function is really > hot. > I don't see it at all. Westmere, 4-way guest. -- error compiling committee.c: too many arguments to function