Re: [libvirt] [RFC] kvm: x86: export vCPU halted state to sysfs
(CCing qemu-devel)
On Fri, Feb 02, 2018 at 09:21:59AM -0500, Luiz Capitulino wrote:
On Fri, 2 Feb 2018 14:19:38 +0000
Daniel P. Berrangé <berrange(a)redhat.com> wrote:
> On Fri, Feb 02, 2018 at 12:15:54PM -0200, Eduardo Habkost wrote:
[...]
> > It would be also interesting to update QEMU QMP
documentation to
> > clarify the arch-specific semantics of "halted".
>
> Any also especially clarify the awful performance implications of running
> this particular query command. In general I would not expect query-xxx
> monitor commands to interrupt all vcpus, so we should clearly warn about
> this !
Or deprecate it...
We could deprecate the expensive fields on query-cpus, and move
them to a more expensive query-cpu-state command. I believe most
users of query-cpus are only interested in qom_path, thread_id,
and topology info.
Markus, Eric: from the QAPI point of view, is it OK to remove
fields between QEMU versions, as long as we follow our
deprecation policy?
--
Eduardo