From mboxrd@z Thu Jan  1 00:00:00 1970
From: Glauber Costa <glommer@redhat.com>
Subject: Re: migrate_set_downtime bug
Date: Tue, 6 Oct 2009 14:33:25 -0300
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Cc: Avi Kivity <avi@redhat.com>,
	Anthony Liguori <anthony@codemonkey.ws>,
	kvm <kvm@vger.kernel.org>
To: Dietmar Maurer <dietmar@proxmox.com>
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On Tue, Oct 06, 2009 at 10:30:14AM +0200, Dietmar Maurer wrote:
> > > 'bandwidth' is something that changes dynamically (or by user
> > settings), so why don't we simply abort after some amount of
> > transferred memory (constant * memory size). This can be implemented by
> > the management application without problems, although it's much easier
> > inside kvm.
> > >
> > Easier, yes.
> > 
> > But then once it is done, people wanting a different behaviour for some
> > valid reason are stuck with that.
> > This is the very reason we expose information about migration in the
> > monitor to begin with.
> 
> No problem. Maybe you can just commit the first part of my patch then?
Anthony should do it.
Given the circumnstances: your method and the current method are both approximations.
Your works where current fails, and none of us can come up with a better solution,
I ack it.

> 
> > Again, I believe the fix for this convergence problem does not belong
> > here.
> 
> The default downtime is set to 30ms. This value triggers the convergence problem quite often. Maybe a longer default is more reasonable.
What do you feel about 100 ms?