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Re: [Xen-devel] VCPU cores & sockets

To: Jean Guyader <jean.guyader@xxxxxxxxxxxxx>
Subject: Re: [Xen-devel] VCPU cores & sockets
From: Ben Guthro <bguthro@xxxxxxxxxxxxxxx>
Date: Tue, 17 Jun 2008 11:52:05 -0400
Cc: xen-devel <xen-devel@xxxxxxxxxxxxxxxxxxx>
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so...if I read your patch, and the intel manual properly -
CPUID.4:EAX[31:26] + 1 is the number of cores...

...
#           '4:eax=0x3,ebx=0x0,ecx=0x0,edx=0x0',
#  '0x80000000:eax=0x3,ebx=0x0,ecx=0x0,edx=0x0']
...

This would set the EAX of leaf 4 to 3 - indicating a dual core processor?

Am I understanding that config file correctly?

Jean Guyader wrote on 06/17/2008 10:44 AM:
Ben Guthro wrote:
Before I get to entrenched in the ACPI code - I thought I'd ping the community to make sure nobody else has investigated this already -

Can we present cores vs sockets for guest VCPUs?
Right now, the number of total processors can be specified, but can we specify cores per socket?

I see this potentially being an hvmloader function, as part of its acpi build code.
Could this be accomplished more generally?


Ben,

This already exists, It's supported via a CPUID configuration.
Right now there are just some comments in the xmexample.hvm file.

I think it would be better to have an entry in the config file like you suggest. I will work on that.

Cheers,


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