From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeremy Fitzhardinge <jeremy@goop.org>
Subject: Re: Xen timing mode
Date: Tue, 23 Feb 2010 12:28:26 -0800
Message-ID: <4B843A6A.5050102@goop.org>
References: <5c3550fe1002230912j1a5d0650oa1e355652c8e3062@mail.gmail.com>	<C7A9BE50.B018%keir.fraser@eu.citrix.com>
	<5c3550fe1002230929r37d1bd73mdd82fc84ee51d0fd@mail.gmail.com>
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To: Priya <pbhat@acis.ufl.edu>
Cc: "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>, Keir Fraser <keir.fraser@eu.citrix.com>
List-Id: xen-devel@lists.xenproject.org

On 02/23/2010 09:29 AM, Priya wrote:
> The Xen Interface manual for Xen v2.0 (attached) Page 4 defines Domain 
> - virtual time as
>
> " The time that progresses at the same pace as system time, but only 
> while a domain is executing -- it stops while a domain is 
> de-scheduled. Therefore the share of the CPU that a domain receives is 
> indicated by the rate at which its virtual time increases."
>
> I am interesting in finding out if any of the timing system 
> calls/instructions like gettimeofday(), hwclock(), rdtsc() can read 
> this domain virtual time.

/proc/stat publishes stolen time for each vcpu (second-last column on 
the "cpuX" lines); you can subtract that from monotonic time to work out 
how much vcpu the domain has got.

     J