From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [PATCH v2 0/2] kvm: x86 CPU power management
Date: Fri, 15 Jun 2018 17:15:33 +0300
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Cc: Eduardo Habkost <ehabkost@redhat.com>, kvm@vger.kernel.org,
	Marcelo Tosatti <mtosatti@redhat.com>, qemu-devel@nongnu.org,
	Richard Henderson <rth@twiddle.net>
To: Paolo Bonzini <pbonzini@redhat.com>
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On Thu, Jun 14, 2018 at 10:32:00PM +0200, Paolo Bonzini wrote:
> On 14/06/2018 17:44, Daniel P. Berrang=E9 wrote:
> >> "-cpu" is certainly wrong for KVM_CAP_X86_DISABLE_EXITS. "-cpu" is a
> >> device option, while this is about host behavior.  "-realtime"'s nam=
e is
> >> awful, but I still think it's the best place for this option.  Maybe=
 we
> >> could call it "-realtime power-mgmt=3D{host|guest}".
> > If none of the existing ones are a suitable fit, then we should just
> > introduce a new CLI arg instead stuffing it into somewhere odd.
>=20
> It is related to mlock in my opinion.  Both options are about applying
> settings that reduce latency but may not be applicable in general.

I would add, it's also about host resource handling.

With mlock guest memory is locked so there's no memory overcommit.
With cpu-pm guest does not give up host cpu which mostly disables
host cpu overcommit.


> Maybe "-realtime" could be renamed to "-perftune" or something like
> that, but I'd like to keep the grouping.
>=20
> Paolo

-overcommit ?

> > IOW, why not just "--power-mgmt host|guest"