+++ This bug was initially created as a clone of Bug #1056037 +++ ...snip... --- Additional comment from Eric Harney on 2014-01-21 13:57:22 EST --- The basic problem here is that Cinder has a fixed time out when waiting for snapshot_delete operations on the Nova side to complete. If they take too long (even when things are functioning correctly) Cinder will prematurely fail the operation. To fix this, we need to have Nova send back updates of job percent complete while the block job is in-progress. Cinder can then reset its timeout window based on these updates. (This should be doable without changing how the APIs work between Cinder and Nova today.)
Moving along with bug 1056037.
why does it take so long to delete a snapshot? Does it have to scrub the snapshot file before deleting it for security reasons?
(In reply to Ben England from comment #3) We are forced to do a blockRebase rather than a commit when deleting the only remaining snapshot, which means the full volume data must be copied. This is a libvirt limitation.
This likely indicates using a version of libvirt which had known bugs in it in this area. Closing pending further info on reproduction.