From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: time accounting problem in pvops kernel
Date: Wed, 18 Aug 2010 09:49:28 +0200
Message-ID: <4C6B9088.5040203@redhat.com>
References: <4C6AC705.1080904@redhat.com> <4C6B1276.9060203@goop.org>
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To: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Glauber Costa <glommer@redhat.com>, "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>
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On 08/18/2010 12:51 AM, Jeremy Fitzhardinge wrote:
>   On 08/17/2010 10:29 AM, Paolo Bonzini wrote:
>> Hi,
>>
>> while experimenting a bit with time.c we found a bug in time
>> accounting.  Basically, /proc/stat counts idle time twice for PV guests
>> running a pvops kernel
>
> What version?

I was using the latest RHEL6 snapshot + the 16-patch blkfront series 
(i.e. without the patch you pointed out).

> Upstream and stable kernels contain the changeset "xen:
> drop xen_sched_clock in favour of using plain wallclock time" which
> should fix a lot of timekeeping/scheduling problems.

I'll try this patch; however, offhand I don't see how it fixes the 
problem of calling account_idle_ticks twice.

Paolo