From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jan Kiszka <jan.kiszka@siemens.com>
Subject: Re: qemu-kvm upstreaming: Do we want
	-kvm-shadow-memory semantics?
Date: Wed, 25 Jan 2012 13:10:38 +0100
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Cc: Marcelo Tosatti <mtosatti@redhat.com>, qemu-devel <qemu-devel@nongnu.org>,
	kvm <kvm@vger.kernel.org>
To: Avi Kivity <avi@redhat.com>
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On 2012-01-25 13:04, Avi Kivity wrote:
> On 01/25/2012 01:57 PM, Jan Kiszka wrote:
>>>
>>> -kvm-shadow-memory is becoming less meaningful for ordinary workloads
>>> since everything uses TDP these days.  It's still meaningful for testing
>>> (forcing aggressive cache replacement), or perhaps nested virtualization.
>>
>> So, is it used for testing in fact? 
> 
> It is not, but it should be.  There's an extra_params option in
> autotest, I'll start using it to stress the mmu some more, even though
> it's going to slow things down for me.

OK.

> 
>> Would a machine option
>> "kvm_shadow_memory=n" be desirable?
> 
> Not sure, this is a host option, not a guest option.  Machine options
> should be guest-visible.

machine options are not guest visible. Basically, this options falls
into the same category as kernel_irqchip.

Do we have alternatives? A top-level command line options is surely none.

Jan

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