Re: [Qemu-devel] Question about dirty page statistics for live migration

[Li Qiang]

2018-08-13 17:35 GMT+08:00 Dr. David Alan Gilbert <address@hidden>:

> * Li Qiang (address@hidden) wrote:
> > Hello Dave, Juan and all,
> >
> > It is useful to get the dirty page rates in guest to evaluate the guest
> > loads
> > so that we can make a decide to live migrate it or not. So I think we can
> > add a on-demand qmp for showing the dirty page rates.
> >
> > I found someone has done this work in here:
> > -->https://github.com/grivon/yabusame-qemu-dpt
> > and here:
> > https://github.com/btrplace/qemu-patch
> >
> > But seems not go to the upstream.
> >
> > I want to know your opinions about adding this qmp.
>
> Something like that could be good;

one easy idea we had was
> a 'migrate null:' uri and then you would use most of the existing
> migration code to do the measurement; you would only have to
> add a dummy file backend,


As far as I understand, here dummy file backend just means the file migrate
to, right?

Thanks,
Li Qiang



> and something to stop the migration ever
> terminating (maybe just set the downtime very low).
>
>
> Dave
>
>
> > Thanks,
> > Li Qiang
> --
> Dr. David Alan Gilbert / address@hidden / Manchester, UK
>