[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

RE: [Xen-devel] [RFC] Physical hot-add cpus and TSC

Yes, I'm confused by this also.
It will takes to this weekend so that I can try it again.


>-----Original Message-----
>From: Dan Magenheimer [mailto:dan.magenheimer@xxxxxxxxxx]
>Sent: Tuesday, June 01, 2010 8:31 AM
>To: Jiang, Yunhong; Keir Fraser; Xen-Devel (xen-devel@xxxxxxxxxxxxxxxxxxx); Ian
>Subject: RE: [Xen-devel] [RFC] Physical hot-add cpus and TSC
>> BTW, I notice one more thing, when system booting w/o hotplug, the warp
>> is 0. However, after I return back after weekend, I noticed the warp is
>> 182. Because I did the hotplug action before getting the warp, I'm not
>> sure if it's caused by the hotplug action, or the system TSC will drift
>> very slowly.
>>  (XEN) TSC marked as reliable, warp = 182 (count=2)
>Hmmm... I'm much more worried about this case and would
>like to understand this better.  If this is reproducible
>on real-world QPI systems, and there is no way to a priori
>determine that "this is a system where even though the
>Invariant TSC bit is set, this system may drift", then
>there is no way Invariant TSC can be exposed to a guest.
>/me can hear Jeremy biting his tongue hard to avoid
>saying "I told you so". ;-)

Xen-devel mailing list



Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.