Re: [Qemu-devel] [Bug 1120383] Re: incremental live block migration of qemu 1.3.1 doesn't work

[Stefan Hajnoczi]

On Sun, Feb 10, 2013 at 3:48 AM, Reno Gan <address@hidden> wrote:
> Another thing i want to mention about live block migration, though i
> don't know if this is really an issue of qemu or downstream libvirt.
>
> When I was testing live migration of qemu-kvm-1.2.0 for long run, i
> found a problem that block data are not completed transferred to target
> host.  I traced that and found block migration thinks migration is
> completed when "block_mig_state.submitted == 0",  but actually in some
> cases, data are not really transferred yet.
>
> I think the reasonable judgement for whether block migration is
> completed is "block_mig_state.submitted == 0 &&
> block_mig_state.read_done == 0", that is all data have been transferred.
>
> I don't see anything about this in block-migration-fixes-for-1.4. Maybe
> it has been addressed somewhere else, but if it is not, please consider
> this issue and make sure data is integrated during block migration.

Is there a way to reproduce this issue easily?

How do you know that not all data has been transferred?

Stefan