Re: Re: c/s 21118: Magny-Coure breakage

[Andre Przywara <andre.przywara@amd.com>]

Dan Magenheimer wrote:
> A large number of software licensing beancounters in the industry
> are going to be busy on this one ;-)
Yes, but do they use the Xen hypervisor interface for that? And do they 
look at the actual socket number? As far as I remember some companies 
;-) are counting MCMs twice, so actually counting the nodes?

> Christophe, can you comment on how Linux and/or other bare metal
> operating systems will be reporting the Magny Cours hierarchy?
As long as there is no such notion as 'sockets per node' (which isn't on 
Linux), everything is fine. It will just report 8 nodes with 6 cores 
each (in case of a 4 socket M-C). Each core has a associated physical 
package id, which is just the same for 12 cores or 2 nodes.
I have a machine here up and running, so just tell me what sysfs path 
you are interested in and I can send you the output.

> I'd hope that Xen could follow their lead on this rather
> than forge new ground, which may result in an incompatible
> implementation.
Until c/s 21118 Xen was just fine, reporting 8 nodes, 4 sockets and 48 
cores. It is just this socket per node (which got removed some years 
ago), which is doing harm. (BTW: I already complained about that last 
year, when Nitin's patch first appeared on the ML).

Regards,
Andre.

-- 
Andre Przywara
AMD-Operating System Research Center (OSRC), Dresden, Germany
Tel: +49 351 448-3567-12