Re: [Qemu-devel] [PATCH 2/3] Add migrate -u option for -incoming pause

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

* Eric Blake (eblake@redhat.com) wrote:
> On 02/10/2015 09:47 AM, Daniel P. Berrange wrote:
> > On Tue, Feb 10, 2015 at 04:16:38PM +0000, Dr. David Alan Gilbert (git) wrote:
> >> From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
> >>
> >> Once a qemu has been started with -incoming pause   the
> 
> s/pause   the/pause, the/
> 
> >> migration can be started by issuing:
> >>
> >> migrate -u uri
> >>
> >> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
> >> ---
> > 
> > Hmm, the 'unpause' codepath doesn't really share anything with the existing
> > codepath. Also the URIs for the existing migrate command are not quite the
> > same as the URIs for the incoming migrate side. This would suggest to me
> > that it might be better to have a separate 'migrate-incoming' command in
> > the monitor rather than overload the existing 'migrate' command.
> > 
> > Also having a separate command will make it possible to detect that this
> > feature is supported from libvirt, since I don't think QMP introspection
> > provides enough info to detect it based on the new arg to existing
> > commands.
> 
> Agree, a new command for QMP would be better (it serves as both the new
> command to use, and the witness that the '-incoming pause:' command line
> works).  The HMP 'migrate -u' is just fine, though (it's fine to have a
> single HMP command smart enough to call out to two different QMP commands).

I've split it out as you all suggested;  I made it migrate-incoming and
also made an HMP migrate_incoming; although as you say you can merge them,
I just find it easier when they match - if you're used to using an HMP
command it's easier when you need to find the matching QMP command.

Dave

> 
> -- 
> Eric Blake   eblake redhat com    +1-919-301-3266
> Libvirt virtualization library http://libvirt.org
> 


--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK