From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <bonzini@gnu.org>
Subject: Re: CPU Overcommitting question
Date: Fri, 18 Jul 2014 23:30:15 +0200
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References: <53C91BF3.6030507@dnshosting.it> <53C93D9D.3010503@redhat.com> <705c3521045351691bbb7e00f52de710@dnshosting.it>
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Cc: kvm@vger.kernel.org, Paolo Bonzini <paolo.bonzini@gmail.com>
To: riccardo.brunetti@dnshosting.it,
	Paolo Bonzini <pbonzini@redhat.com>
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Il 18/07/2014 18:49, riccardo.brunetti@dnshosting.it ha scritto:
> So, it should be ok to have the first two options, but also considering
> that with hyperthreading instead of 12 cores we can consider 24? Thus we
> can go with:
> 
> 1) Assign vCPUs so that vCPU(VM1) + vCPU(VM2) = total number of cores
> (24) (both VMs have < 24 vCPUs) (ie. 18+6)
> 2) Assign vCPUs so that vCPU(VM1) + vCPU(VM2) > total number of cores
> (24) (both VMs have <= 24 vCPUs) (ie. 24+10)

Yes.

Something between 12 and 24 will probably give the best performance.

Paolo