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Re: [Xen-devel] Xen CPU limit?

To: "Martin Lukasik" <martin.lukasik@xxxxxxxxxxxxx>, "Pasi Kärkkäinen" <pasik@xxxxxx>
Subject: Re: [Xen-devel] Xen CPU limit?
From: "Jan Beulich" <JBeulich@xxxxxxxxxx>
Date: Tue, 30 Mar 2010 08:16:26 +0100
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>>> Pasi Kärkkäinen<pasik@xxxxxx> 29.03.10 17:49 >>>
>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.

I don't think the tools are up to anything beyond 32 yet. The (64-bit)
hypervisor allows up to 8192 vCPU-s iirc (but that's a truly
theoretical limit, as Dom0 or a guest likely won't be able to bring up
that many due to there only being 4096 event channels; current
Linux requires 5-6 of them per vCPU for IPIs and timer vIRQ).


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