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Re: [Xen-devel] Question about vcpu_avail

To: Michal Novotny <minovotn@xxxxxxxxxx>
Subject: Re: [Xen-devel] Question about vcpu_avail
From: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Date: Tue, 24 Nov 2009 15:05:07 +0000
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On 24/11/2009 14:51, "Michal Novotny" <minovotn@xxxxxxxxxx> wrote:

>> We already have a config option for that, called 'vcpus'. 'vcpu_avail' can
>> then be used to limit the number of those which are brought online during
>> initial boot. Any new config-file options can be sugar on top of those.
> Well, imagine scenario you need to allocate 4 vcpus to the guest but you
> need to use only 2 vcpus at startup. So you suggest having `vcpus` and
> `maxvcpus` options in the config file and allocating all the `maxvcpus`
> and setting number of `vcpus` by setting appropriate mask using
> `vcpu_avail` ?

Yeah, I think you get it. In your example: if the user specifies maxvcpus=4,
vcpus=2 then xm turns that into vcpus=4, vcpu_avail=3 before sending it to

 -- Keir

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