[libvirt] [RFC] live migration of VMs with internal snapshots

[Maxim Nestratov]

Hi,

As far as I understand, currently there is no way to live migrate qemu 
VMs that
have internal snapshots, because live migration works via qemu drive 
mirroring,
which in turns mirrors only shallow block layer, effectively losing 
existing embedded
snapshots. The problem could be fixed if we created an external delta 
for all disks with
internal snapshots, live migrate such VMs and then auto merge them back into
original images. That said, I would like to know very much your opinion 
on the matter
and would also like to know if this approach is affordable. If so, I or 
one of my colleagues
will send a pathset to fix this, otherwise what solution for this 
problem you will
recommend?

Thanks,
Maxim