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Re: [OpenStack] Guest OS shows just one CPU core instead of two

 

On Tue, Mar 05, 2013 at 04:00:06PM +0530, Balamurugan V G wrote:
> Hi,
> 
> I am running Folsom 2.2 with a KVM compute node. When I launch a windows
> instance with flavor that has 2 VCPUs and 2Gb RAM, the guest seems the RAM
> fine but not the 2 CPUs. It reports only one Virtual processor. Whne I look
> at the command line options with which KVM has launched the instance, I see
> that in -smp argument, sockets is set to 2 and core is set to 1. How can I
> get the core to be 2 so that the guest OS can see it?

There's nothing wrong with what the command line set here. It is
simply configuring 2 vCPUS where each vCPU is represented as a
separate socket to the guest, rather than what you describe which
would be 1 socket with dual-cores.

You don't mention what Windows version you are using, but some versions
are not clever enough to switch between a uniprocessor config and SMP
config. So if you installed those versions on a 1 CPU guest, then even
if you later boot the image on 1 CPU guest, it won't see the extra CPUs.
There are hacks you can do to "upgrade" a windows install from the
uniprocessor to multiprocessor HAL - see the microsoft kbase for more
info

Regards,
Daniel
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