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Re: [Xen-devel] Xen CPU limit?

To: Martin Lukasik <martin.lukasik@xxxxxxxxxxxxx>
Subject: Re: [Xen-devel] Xen CPU limit?
From: Pasi Kärkkäinen <pasik@xxxxxx>
Date: Mon, 29 Mar 2010 18:49:01 +0300
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On Thu, Mar 11, 2010 at 04:08:38PM +0000, Martin Lukasik wrote:
> Hello,
> Can somebody explain why the number of CPUs Xen can handle is limited to 32?
> I have a machine with 48 cores, and would love to virtualise it, but if  
> I do it, I loose 16 CPUs, which isnt very good... :-(
> Where is this limit coming from? Or maybe it is possible to change it  
> somewhere in the source files?

I think the number of virtual cpus (vcpus) per guest is (was) 32,
and now in Xen 4.0.0 you can have up to 64 vcpus per guest.

The max number of physical cpus is 128 or so..

-- Pasi

> Cheers,
> Martin
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