Re: [Qemu-devel] [RFC PATCH RDMA support v5: 03/12] comprehensive protocol documentation

[Michael R. Hines]

On 04/15/2013 04:28 AM, Paolo Bonzini wrote:
> Il 15/04/2013 03:06, Michael R. Hines ha scritto:
> > > > > > Next, decide if you want dynamic page registration on the server-side.
> > > > > > For example, if you have an 8GB RAM virtual machine, but only 1GB
> > > > > > is in active use, then disabling this feature will cause all 8GB to
> > > > > > be pinned and resident in memory. This feature mostly affects the
> > > > > > bulk-phase round of the migration and can be disabled for extremely
> > > > > > high-performance RDMA hardware using the following command:
> > > > > > QEMU Monitor Command:
> > > > > > $ migrate_set_capability chunk_register_destination off # enabled
> > > > > > by default
> > > > > >
> > > > > > Performing this action will cause all 8GB to be pinned, so if that's
> > > > > > not what you want, then please ignore this step altogether.
> > > > > This does not make it clear what is the benefit of disabling this
> > > > > capability. I think it's best to avoid options, just use chunk
> > > > > based always.
> > > > > If it's here "so people can play with it" then please rename
> > > > > it to something like "x-unsupported-chunk_register_destination"
> > > > > so people know this is unsupported and not to be used for production.
> > > > Again, please drop the request for removing chunking.
> > > >
> > > > Paolo already told me to use "x-rdma" - so that's enough for now.
> > > You are adding a new command that's also experimental, so you must tag
> > > it explicitly too.
> > The entire migration is experimental - which by extension makes the
> > capability experimental.
> You still have to mark it as "x-".  Of course not "x-unsupported-", that
> is a pleonasm.
>
> Paolo

Sure, I'm happy add another 'x'. I will submit a patch with all the new
changes as soon as the pull completes.

- Michael