Re: [Qemu-devel] [PATCH V2] balloon: Don't try fetching info if machine is stopped

[Daniel P. Berrange]

On Thu, Aug 26, 2010 at 01:47:50PM +0530, Amit Shah wrote:
> On (Thu) Aug 26 2010 [10:05:44], Paolo Bonzini wrote:
> > On 08/26/2010 08:05 AM, Amit Shah wrote:
> > >This is what I have currently. It would need some timer handling in
> > >the save/load case as well, right?
> > 
> > When loading you won't have any pending "info balloon" command, so I
> > think the timer need not be preserved across migration.
> > 
> > Also, 5 seconds for a stopped guest is actually a lot,
> 
> That's the problem; it's policy. Where and how to specify it?

It is unfortunate that this is policy, but we just have to accept
that the current query-balloon command is a flawed design. IMHO
we  should just hardcode the timeout at 5 seconds as you do (plus
immediate return for paused guests). Then focus on adding new 
monitor commands/events to deal with balloon query in a way 
that doesn't require this kind of policy in QEMU, and deprecate 
the existing query-balloon command.

REgards,
Daniel
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