From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: kvm guest: hrtimer: interrupt too slow Date: Mon, 05 Oct 2009 12:47:14 +0200 Message-ID: <4AC9CEB2.70600@redhat.com> References: <4AC207B1.7020901@msgid.tls.msk.ru> <4AC20FDB.2050607@redhat.com> <4AC212A3.2050204@msgid.tls.msk.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: kvm , Glauber Costa To: Michael Tokarev Return-path: Received: from mx1.redhat.com ([209.132.183.28]:50117 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932362AbZJEKrq (ORCPT ); Mon, 5 Oct 2009 06:47:46 -0400 In-Reply-To: <4AC212A3.2050204@msgid.tls.msk.ru> Sender: kvm-owner@vger.kernel.org List-ID: On 09/29/2009 03:58 PM, Michael Tokarev wrote: > Avi Kivity wrote: >> On 09/29/2009 03:12 PM, Michael Tokarev wrote: > [] >>> The thing is that after some uptime, kvm >>> guest prints something like this: >>> >>> hrtimer: interrupt too slow, forcing clock min delta to 461487495 ns > [] >> What happens if you use hpet or pmtimer as guest clocksource? > > For all the guests I have handy, only 2 clocksources > are available: kvm-clock and acpi_pm. The host itself > has hpet turned off because it itself had issues with > hpet, and after many tries we finally turned it off > (there were several long and painy threads on lkml > about this). > > Dunno why pmtimer isn't available. acpi_pm is pmtimer. > > I tried switching to acpi_pm on a running guest (which > is still runnining in very slow mode), but that did not > make any difference - i.e., it did not become "fast" > again. > >> Please post host /proc/cpuinfo. > > Here's the cpuinfo from host (for last core): > > flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge > mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext > fxsr_opt pdpe1gb rdtscp lm 3dnowext 3dnow constant_tsc rep_good > nonstop_tsc extd_apicid pni monitor cx16 popcnt lahf_lm cmp_legacy svm > extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs Has both constant_tsc and nonstop_tsc, wonder why it's making so much trouble. -- error compiling committee.c: too many arguments to function