From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH 18/21] Remove host_alarm_timer hacks. Date: Thu, 30 Apr 2009 18:46:03 +0300 Message-ID: <49F9C7BB.1080908@redhat.com> References: <1241040038-17183-1-git-send-email-aliguori@us.ibm.com> <1241040038-17183-19-git-send-email-aliguori@us.ibm.com> <49F972EB.3040208@redhat.com> <49F9A56C.5000705@us.ibm.com> <49F9A6BA.5040702@redhat.com> <49F9A97D.7050004@us.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org To: Anthony Liguori Return-path: Received: from mx2.redhat.com ([66.187.237.31]:37662 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932848AbZD3PqI (ORCPT ); Thu, 30 Apr 2009 11:46:08 -0400 In-Reply-To: <49F9A97D.7050004@us.ibm.com> Sender: kvm-owner@vger.kernel.org List-ID: Anthony Liguori wrote: > Avi Kivity wrote: >> Anthony Liguori wrote: >>> In modern KVM, the IO thread is capable of interrupting the CPU >>> whenever it needs to process IO. Therefore this "problem" no longer >>> exists. >>> >> >> It would still be good to verify that the problem no longer exists. >> This is not a cosmetic change; some testing is needed to verify it >> doesn't introduce new latencies. >> > > N.B. dynticks is the preferred timer in QEMU on Linux. To even hit > this code path, you'd have to use an explicit -clock hpet or -clock > rtc. I don't have an hpet on my laptop and -clock rtc boots just as > fast as it did before. I'll apply this and see what happens. > > Do we really care about optimizing latency with -clock rtc though? > People still run kvm on RHEL 5 (or cheap clones thereof), aren't they affected? -- error compiling committee.c: too many arguments to function