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Date: Tue, 12 Jan 2010 09:07:17 -0600
From: Anthony Liguori <anthony@codemonkey.ws>
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Subject: Re: [Qemu-devel] Re: [PATCH 4/4] Try not to exceed max downtime on
	stage3
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To: Jan Kiszka <jan.kiszka@siemens.com>
Cc: qemu-devel@nongnu.org, Liran Schour <lirans@il.ibm.com>

On 01/12/2010 05:51 AM, Jan Kiszka wrote:
> Liran Schour wrote:
>    
>> Move to stage3 only when remaining work can be done below max downtime.
>> To make sure the process will converge we will try only MAX_DIRTY_ITERATIONS.
>>      
> OK, that explains now patch 2. But do we have such barrier for memory
> migration as well?

No, we explicitly don't because making that decision is a management 
tool job.

A management tool can force convergence by explicitly stopping the guest.

Iterations is a bad metric because there's no real useful meaning to a user.

Time is probably the best metric and it's easy for a management tool to 
set a timer to stop the guest if it hasn't completed by a certain time 
period.

Regards,

Anthony Liguori