[libvirt] [PATCH 11/19] qemu: Migration job on source daemon

[Jiri Denemark]

On Tue, Jul 12, 2011 at 12:18:41 +0100, Daniel P. Berrange wrote:
> On Fri, Jul 08, 2011 at 01:34:16AM +0200, Jiri Denemark wrote:
> > Make MIGRATION_OUT use the new helper methods.
> > 
> > This also introduces new protection to migration v3 process: the
> > migration job is held from Begin to Confirm to avoid changes to a domain
> > during migration (esp. between Begin and Perform phases). This change,
> > however brings a small issue when Prepare step fails during normal (not
> > p2p or tunneled) migration when old client talks to new libvirtd. The
> > old client doesn't call Confirm (with cancelled == 1) to end the
> > migration job. I'm open to suggestions how to solve this in the best
> > way. My idea is to use flags for Begin3 and Perform3 that would enable
> > this extra protection by moving migration job start from Perform to
> > Begin phase while maintaining the old behavior if the flags are not set.
> > Note that virDomainAbortJob will be able to cancel migration in any
> > phase (i.e., not only in Perform phase).
> 
> What do you mean by 'old client' in this context ?  A v3 migration
> client from the 0.9.3 release, or a v2 migration client from a
> < 0.9.3 release

V3 migration client from 0.9.3. V2 migration is ok in this aspect since it has
no Begin API (but that, on the other hand, means that the domain can change
between DumpXML and Perform).

Jirka