Re: [PATCH v10 11/12] migration/dirtyrate: Implement qmp_cal_dirty_rate()/qmp_get_dirty_rate() function

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Eric Blake (eblake@redhat.com) wrote:
> On 9/16/20 1:22 AM, Chuan Zheng wrote:
> > Implement qmp_cal_dirty_rate()/qmp_get_dirty_rate() function which could be called
> > 
> > Signed-off-by: Chuan Zheng <zhengchuan@huawei.com>
> > ---
> 
> > +++ b/qapi/migration.json
> > @@ -1737,3 +1737,53 @@
> >   ##
> >   { 'enum': 'DirtyRateStatus',
> >     'data': [ 'unstarted', 'measuring', 'measured'] }
> > +
> > +##
> > +# @DirtyRateInfo:
> > +#
> > +# Information about current dirty page rate of vm.
> > +#
> > +# @dirty-rate: @dirtyrate describing the dirty page rate of vm
> > +#          in units of MB/s.
> > +#          If this field return '-1', it means querying is not
> > +#          start or not complete.
> 
> Grammar:
> 
> it means querying has not yet started or completed.
> 
> Should this field instead be optional, and omitted for those cases?  In
> which case, I'd suggest:
> 
> ...in units of MB/s, present only when querying the rate has completed.

I've already got it queued; I'll fix up the grammar; if someone wants to
send a change to make it optional before this version freezes that's OK.

Dave

> 
> > +#
> > +# @status: status containing dirtyrate query status includes
> > +#          'unstarted' or 'measuring' or 'measured'
> > +#
> > +# @start-time: start time in units of second for calculation
> > +#
> > +# @calc-time: time in units of second for sample dirty pages
> > +#
> > +# Since: 5.2
> > +#
> > +##
> > +{ 'struct': 'DirtyRateInfo',
> > +  'data': {'dirty-rate': 'int64',
> > +           'status': 'DirtyRateStatus',
> > +           'start-time': 'int64',
> > +           'calc-time': 'int64'} }
> > +
> > +##
> > +# @calc-dirty-rate:
> > +#
> > +# start calculating dirty page rate for vm
> > +#
> > +# @calc-time: time in units of second for sample dirty pages
> > +#
> > +# Since: 5.2
> > +#
> > +# Example:
> > +#   {"command": "calc-dirty-rate", "data": {"calc-time": 1} }
> > +#
> > +##
> > +{ 'command': 'calc-dirty-rate', 'data': {'calc-time': 'int64'} }
> > +
> > +##
> > +# @query-dirty-rate:
> > +#
> > +# query dirty page rate in units of MB/s for vm
> > +#
> > +# Since: 5.2
> > +##
> > +{ 'command': 'query-dirty-rate', 'returns': 'DirtyRateInfo' }
> > 
> 
> -- 
> Eric Blake, Principal Software Engineer
> Red Hat, Inc.           +1-919-301-3226
> Virtualization:  qemu.org | libvirt.org
-- 
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK