Re: [Qemu-devel] [PATCH 00/46] Postcopy implementation

[Dr. David Alan Gilbert]

* Paolo Bonzini (address@hidden) wrote:
> Il 04/07/2014 19:41, Dr. David Alan Gilbert (git) ha scritto:
> >   e) I've added a 'migration_set_parameter' command as somewhere to put 
> > integer
> >      parameters associated with migration.
> >      e.1) And I use that initially for the length of precopy to try.
> 
> Could you have instead a "migrate_start_postcopy" command, and leave the
> policy to management instead?

Hmm; yes that is probably possible - although with the migration_set_parameter
configuration you get the best of both worlds:
   1) You can set the parameter to say a few seconds and let QEMU handle it
   2) You can set the parameter really large, but (I need to check) you could
      drop the parameter later and then cause it to kick in.

I also did it this way because it was similar to the way the auto-throttling
mechanism.

> We could also (later) add an event for the end of the migration bulk phase,
> that can help management deciding when to switch?

Yeh, the libvirt people want an event to know when (the existing) migration 
completes,
and this would easily fit onto that.

Dave
--
Dr. David Alan Gilbert / address@hidden / Manchester, UK