From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: high load with usb device Date: Tue, 14 Sep 2010 18:00:35 +0200 Message-ID: <4C8F9C23.4090400@redhat.com> References: <4C80E839.50604@msgid.tls.msk.ru> <4C8A1AE3.8030705@redhat.com> <4C8A2187.1020202@msgid.tls.msk.ru> <4C8A59FE.9090400@msgid.tls.msk.ru> <4C8C9CAA.9030203@redhat.com> <4C8F1B54.60604@msgid.tls.msk.ru> <4C8F3B00.3000703@redhat.com> <4C8F3BA7.7060302@redhat.com> <4C8F47A1.4030600@msgid.tls.msk.ru> <4C8F497C.7000904@redhat.com> <4C8F4DA8.50606@msgid.tls.msk.ru> <4C8F50E1.3060704@redhat.com> <4C8F563E.6070701@msgid.tls.msk.ru> <4C8F757D.1010509@msgid.tls.msk.ru> <4C8F77C1.90509@redhat.com> <4C8F78D6.2060808@msgid.tls.msk.ru> <4C8F8AA2.90403@redhat.com> <4C8F8C5A.9000003@msgid.tls.msk.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: KVM list To: Michael Tokarev Return-path: Received: from mx1.redhat.com ([209.132.183.28]:56451 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753783Ab0INQAm (ORCPT ); Tue, 14 Sep 2010 12:00:42 -0400 In-Reply-To: <4C8F8C5A.9000003@msgid.tls.msk.ru> Sender: kvm-owner@vger.kernel.org List-ID: On 09/14/2010 04:53 PM, Michael Tokarev wrote: > 14.09.2010 18:45, Avi Kivity =D0=BF=D0=B8=D1=88=D0=B5=D1=82: > >> 17:27:23.999996 select(13, [0 5 7 9 10 12], [], [], {1, 0}) =3D 2= (in [5 > >> 10], left {0, 999998})<0.000009> > >> 17:27:24.000199 select(13, [0 5 7 9 10 12], [], [], {1, 0}) =3D 1= (in > >> [12], left {0, 998775})<0.001241> > >> 17:27:24.001666 select(13, [0 5 7 9 10 12], [], [], {1, 0}) =3D 2= (in [5 > >> 10], left {0, 999997})<0.000006> > >> 17:27:24.001768 select(13, [0 5 7 9 10 12], [], [], {1, 0}) =3D 1= (in > >> [12], left {0, 999932})<0.000103> > >> 17:27:24.001985 select(13, [0 5 7 9 10 12], [], [], {1, 0}) =3D 2= (in [5 > >> 10], left {0, 999998})<0.000005> > >> 17:27:24.002061 select(13, [0 5 7 9 10 12], [], [], {1, 0}) =3D 1= (in > >> [12], left {0, 998407})<0.001617> > > > > That pipe is doing a lot of damage (I don't have it, and couldn't > > reproduce your results, another pointer). Do you have CONFIG_EVEN= TFD > > set? If not, why not? > > As I mentioned in other emails in this thread: > > o yes, I do have CONFIG_EVENTFD set, and it is being used > too (fd#12 in the above strace). I thought that was the signalfd. > o 0.13.0-rc1 behaves the same way (that is, it also shows > high load when idle -- the same 18% of host CPU), but it > has no pipe on fd#5. > > I think it's host_alarm_handler()'s use of qemu_notify_event(). It's=20 telling the main loop to rescan pending events, even though it's called= =20 from the main loop itself. Please drop it and rerun. It booted for me and seems to work. Marcelo, it's safe to remove it, yes? (except for tcg or upstream=20 without iothread). --=20 error compiling committee.c: too many arguments to function