On 10.12.25 18:20, Peter Xu wrote:
On Wed, Dec 10, 2025 at 02:41:20PM +0300, Vladimir Sementsov-Ogievskiy wrote:
Yes, it can. And regardless of the way we chose: qdev properties or qapi,
I don't think we need a property for backend itself. We need a property
(or migration capability) for vhost-user-blk itself, saying that its
backend should be migrated.
The problem is then we need to introduce the new property to all frontends
that would support the backend? If it's a backend property, it can be one
property for the backend that all the frontends can consume.
Hmm, agree, that's right.. So, we may not touch frontend at all, and only
setup backend to be migrated. And this remains transparent for frontend side.
It's a lot simpler to migrate backend inside of frontend state. If we
migrate backend in separate, we can't control the order of backend/frontend
stats, and will have to implement some late point in state load process,
where both are already loaded and we can do our post-load logic.
Would MigrationPriority help when defining the VMSD?
Didn't know about it. Most probably it may help, we just setup so that backends
migrate before frontends.
--
Best regards,
Vladimir
