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RE: [Xen-devel] Re: Isolation and time

To: "Keir Fraser" <keir.fraser@xxxxxxxxxxxxx>, "Dave Winchell" <dwinchell@xxxxxxxxxxxxxxx>, "Ben Guthro" <bguthro@xxxxxxxxxxxxxxx>, xen-devel <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: RE: [Xen-devel] Re: Isolation and time
From: "Dan Magenheimer" <dan.magenheimer@xxxxxxxxxx>
Date: Mon, 30 Jun 2008 18:22:19 -0600
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> Yes, I reckon that could work pretty well.
> 
>  -- Keir

I'm pretty sure the attached script when run in
domain0 will generate an appropriately random CPU
load on every domain0 vcpu.  For each vcpu, it
randomly eats CPU for a fraction of a second, then
sleeps for the same amount of time, then repeats.
Thus any timer-under-test domain should see
random unscheduled intervals which hopefully
occur at random fractions of its timer tick.

I'll probably use this for future timer testing,
so let me know if you see problems with this
approach.

Thanks,
Dan

P.S. May be dependent on RH-based dom0.

> -----Original Message-----
> From: Keir Fraser [mailto:keir.fraser@xxxxxxxxxxxxx]
> Sent: Saturday, June 14, 2008 9:25 AM
> 
> <dan.magenheimer@xxxxxxxxxx> wrote:
> 
> > That's what I thought.  Sorry to belabour, but
> > that leads to one more question:
> >
> > If one were to put an appropriately random CPU-only load
> > on every processor on domain0 (assuming domain0 runs
> > on all physical processors), then this would presumably
> > be sufficient to exercise a domain-under-test's time
> > synchronization, correct?
> 
> Yes, I reckon that could work pretty well.
> 
>  -- Keir

Attachment: dom0busy.sh
Description: Text document

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