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Date: Tue, 27 Aug 2013 16:20:09 +0300
From: Gleb Natapov <gleb@redhat.com>
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Subject: Re: [Qemu-devel] KVM guest cpu L3 cache and cpufreq
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To: =?utf-8?Q?Beno=C3=AEt?= Canet <benoit.canet@irqsave.net>
Cc: pbonzini@redhat.com, Igor Mammedov <imammedo@redhat.com>, Eduardo Habkost <ehabkost@redhat.com>, Andreas =?utf-8?Q?F=C3=A4rber?= <afaerber@suse.de>, qemu-devel@nongnu.org

On Tue, Aug 27, 2013 at 04:17:56PM +0300, Gleb Natapov wrote:
> On Tue, Aug 27, 2013 at 03:18:16PM +0200, Beno=C3=AEt Canet wrote:
> >=20
> > Hello Eduardo,
> >=20
> > I read a bit about caches on wikipedia.
> >=20
> > If I understand correctly changing the CPUID L3 cache infos in QEMU wil=
l change
> > the value displayed in the guest /proc/cpuinfo but will not change the =
size of
> > the l3 cache used by the hardware. So I am chasing a cosmetic bug.
> > If it right ?
> >=20
> Right.
>=20
Well, actually not entirely. An application can query cache sizes and
adjust its algorithms accordingly in which case performance can be
suboptimal if information in a guest is not accurate.

--
			Gleb.