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Date: Thu, 5 Jan 2017 08:50:48 -0200
From: Marcelo Tosatti <mtosatti@redhat.com>
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Subject: Re: [Qemu-devel] TSC frequency configuration & invtsc migration
 (was Re: [PATCH 4/4] kvm: Allow migration with invtsc)
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To: Eduardo Habkost <ehabkost@redhat.com>
Cc: qemu-devel@nongnu.org, Paolo Bonzini <pbonzini@redhat.com>, kvm@vger.kernel.org, Haozhong Zhang <haozhong.zhang@intel.com>, libvir-list@redhat.com

On Thu, Jan 05, 2017 at 08:48:32AM -0200, Marcelo Tosatti wrote:
> > Note that even if we follow your suggestion and implement an
> > alternative version of patch 4/4 to cover your use case, I will
> > strongly recommend libvirt developers to support configuring TSC
> > frequency if they want to support invtsc + migration without
> > surprising/unpredictable restrictions on migratability.
> 
> Well, alright. If you make the TSC frequency of the host
> available to mgmt software as you describe, and write the steps mgmt
> software should take, i'm good.
> 
> Thanks for the help Eduardo.
> 

I'll be happy to not have to add a weird script to 

1. Query the host TSC frequency.
2. Pass that to -cpu xxx,tsc-frequency=ZZZ

To my migration scripts. 

Probably easy to make that the default behaviour...