Re: [Qemu-devel] [PATCH 6/6] qmp: add balloon-get-memory-stats & event

[Luiz Capitulino <lcapitulino@redhat.com>]

On Wed, 22 Feb 2012 10:54:45 -0600
Michael Roth <mdroth@linux.vnet.ibm.com> wrote:

> But I'm not suggesting we make query-balloon asynchronous.
> 
> I'm suggesting be re-enable it as a synchronous interface by having it
> immediately return the latest-available results from a timer-driven
> query mechanism that tucks away the query results, such as the one Anthony
> suggested.

I'm not sure I like the semantics, as query-balloon would have some fields
that actually depends on a timer based polling being enabled somewhere else,
while others fields ('actual') would always be there.

> > But that's a dead discussion I guess, as I already agreed on implementing
> > this as a device property.
> 
> Along with timer-based refresh of the properties? If so I don't understand why we
> can't just have query-balloon simply return those properties when it's called? I
> thought that's what Anthony was driving at with the timer-based
> approach.

What I had understood is to make each stats a dynamic device property, then
mngt apps would use qom-set/get on them.

Anthony, can you detail your suggestion please?