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Date: Fri, 12 Dec 2014 17:13:55 +0100
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [dpdk-dev] [PATCH v4 00/10] VM Power Management
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On 12/12/2014 17:10, Thomas Monjalon wrote:
> > Ok, this looks specific enough that an out-of-band solution within DPDK
> > sounds like the best approach.  It seems unnecessary to involve the
> > hypervisor (neither KVM nor QEMU).
>
> Paolo, I don't understand why you don't imagine controlling frequency scaling
> of a pinned vCPU transparently?

Probably because I don't imagine controlling frequency scaling from the
application on bare metal, either. :)  It seems to me that this is just
working around limitations of the kernel.

Paolo

> In my understanding, we currently cannot control frequency scaling without
> knowing wether we are in a VM or not.