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Date: Thu, 11 Dec 2014 14:44:17 +0000
From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Message-ID: <20141211144416.GH2567@work-vm>
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Subject: Re: [Qemu-devel] migration from qemu2.1.2 to qemu2.2
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To: William Dauchy <william@gandi.net>
Cc: QEMU Developers <qemu-devel@nongnu.org>

* William Dauchy (william@gandi.net) wrote:
> On Dec11 14:34, Dr. David Alan Gilbert wrote:
> > > I dont get your last statement;
> > > my common use case is to live migrate an old userland to a new one
> > > (so 2.1 to 2.2 here); so if I guarantee same HW, it should work, right?
> > 
> > I wouldn't trust -host cpu  to be the same on the same HW between
> > different QEMUs, especially on newer hardware than your older QEMU new
> > about.
> 
> understood.
> What are your recommendations then? Using kvm64 proc?

I'd recommend doing -cpu help on your oldest qemu  and pick the CPU that's
as new as possible but not newer than your oldest hardware.

Dave

> 
> Thanks for your feedback,
> -- 
> William


--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK