From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.fraser@eu.citrix.com>
Subject: Re: xen tsc problems?
Date: Tue, 13 Jul 2010 18:48:19 +0100
Message-ID: <C8626573.1A92C%keir.fraser@eu.citrix.com>
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To: Stefano Stabellini <Stefano.Stabellini@eu.citrix.com>, Dan Magenheimer <dan.magenheimer@oracle.com>
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On 13/07/2010 18:39, "Stefano Stabellini" <Stefano.Stabellini@eu.citrix.com>
wrote:

> I started to wonder why the guest is seeing such a big tsc warp when xen
> is seeing 0, so I added more tracing and eventually I found out that the
> value of v->arch.hvm_vcpu.stime_offset is significantly different
> between the two vcpus and the difference increases after the scaling.
> Then I added timer_mode=1 to my vm config file and the problem went
> away.
> I think that delay_for_missed_ticks shouldn't cause tsc scew in
> the guest.

Well, timer_mode=1 is the default and I doubt in all seriousness that the
other modes get any use or testing.

 -- Keir