[sheepdog-users] sheepdog replication got stuck

[Liu Yuan]

On Tue, Jan 07, 2014 at 08:13:21AM +0100, Gerald Richter - ECOS wrote:
> Hi,
> 
> I am pretty sure that the VM were I lost the data, had more than 40 MB changed data.
> 
> From what I am seeing here when qemu-img imports the vm is, as long as there is only one import process it works fine. As soon as I am doing multiple imports in parallel the object cache flusher hangs at some point (not always the same point) and nothing gets flushed anymore. When the import is finished qemu-img tries to make a sync, but this hangs because the object cache flush hangs, so the import never ends.

So this highly indicate a object cache bug for parallel importing. But I am
currently busy with other stuff.

Hitoshi, do you have time to dig this problem? If it is reliably reproduciable,
I think it is not hard to solve.

>
> BTW. During the last hour were we are writing emails I was only able to delete three VMs (the fours is still in progress) because recovery is still running (without recovery running it normally takes only a few seconds). Need the vdi be fully recovered before it can be deleted?

This is really a corner case, I think sheepdog should support it well at least
in theory. I'd suggest you try to delete VDI in recovery and see what happens
and report bugs if any.

Thanks
Yuan