Re: [PATCH v2 00/13] migrate/ram: Fix resizing RAM blocks while migrating

[Peter Xu]

On Fri, Feb 21, 2020 at 05:41:51PM +0100, David Hildenbrand wrote:
> I was now able to actually test resizing while migrating. I am using the
> prototype of virtio-mem to test (which also makes use of resizable
> allocations). Things I was able to reproduce:

The test cases cover quite a lot.  Thanks for doing that.

> - Resize while still running on the migration source. Migration is canceled
> -- Test case for "migraton/ram: Handle RAM block resizes during precopy"

> - Resize (grow+shrink) on the migration target during postcopy migration
>   (when syncing RAM blocks), while not yet running on the target
> -- Test case for "migration/ram: Discard new RAM when growing RAM blocks
>    and the VM is stopped", and overall RAM size synchronization. Seems to
>    work just fine.

This won't be able to trigger without virtio-mem, right?

And I'm also curious on how to test this even with virtio-mem.  Is
that a QMP command to extend/shrink virtio-mem?

> - Resize (grow+shrink) on the migration tagret during postcopy migration
>   while already running on the target.
> -- Test case for "migration/ram: Handle RAM block resizes during postcopy"
> -- Test case for "migration/ram: Tolerate partially changed mappings in
>    postcopy code" - I can see that -ENOENT is actually triggered and that
>    migration succeeds. Migration seems to work just fine.

Thanks,

-- 
Peter Xu