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Date: Thu, 12 Apr 2012 07:26:12 +0900
From: Takuya Yoshikawa <takuya.yoshikawa@gmail.com>
To: Avi Kivity <avi@redhat.com>
Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>,
        Marcelo Tosatti <mtosatti@redhat.com>,
        Xiao Guangrong <xiaoguangrong.eric@gmail.com>,
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Subject: Re: [PATCH 00/13] KVM: MMU: fast page fault
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On Wed, 11 Apr 2012 17:21:30 +0300
Avi Kivity <avi@redhat.com> wrote:

> Currently the main performance bottleneck for migration is qemu, which
> is single threaded and generally inefficient.  However I am sure that
> once the qemu bottlenecks will be removed we'll encounter kvm problems,
> particularly with wide (many vcpus) and large (lots of memory) guests. 
> So it's a good idea to improve in this area.  I agree we'll need to
> measure each change, perhaps with a test program until qemu catches up.

I agree.

I am especially interested in XBRLE + current srcu-less.

> > I am testing the current live migration to see when and for what it can
> > be used.  I really want to see it become stable and usable for real
> > services.

> Well, it's used in production now.

About RHEL6 e.g., yes of course and we are ...

My comment was about the current srcu-less and whether I can make it enough
stable in this rc-cycle.  I think it will enlarge real use cases in some
extent.

> > So I really do not want to see drastic change now without any real need
> > or feedback from real users -- this is my point.

> It's a good point, we should avoid change for its own sake.

Yes, especially because live migration users are limited to those who have
such services.

I hope that kernel developers start using it in their desktops!!!???

Thanks,
	Takuya