Tal Nisan has submitted this change and it was merged. Change subject: engine: remove snapshots table constraints ...................................................................... engine: remove snapshots table constraints The RestoreAllSnapshotsCommand is a transactive command. As part of the flow, first the snapshot entry is locked, then if needed memory volumes will be deleted. However, the RemoveDiskCommand is a non-transactive command and when it will try to delete the memory disk, it will need to update also the snapshot row that contains the memory disk id. But since that the snapshot row is already locked by the first command, the RemoveDiskCommand will fail to get the lock. This patch remove the constraints between the base_disks and the snapshots. A better solution is to make RestoreAllSnapshotsCommand a non-transactive command, and add compensation logic. Also, newer version of Postgres will permit better locking, avoiding this situation. Bugs: BZ 1454823: Restore the constraints after upgrading the Postgres version. BZ 1454830: Make RestoreAllSnapshotsCommand non-transactive command and add compensation logic Change-Id: Iffc45d2ef28b65894504e49f6e966c81c4a16c3f Bug-Url: https://bugzilla.redhat.com/1427104 Signed-off-by: Fred Rolland <frolland(a)redhat.com&gt; --- A packaging/dbscripts/upgrade/04_01_0810_drop_memory_snapshot_constraints.sql 1 file changed, 2 insertions(+), 0 deletions(-) Approvals: Tal Nisan: Looks good to me, approved Jenkins CI: Passed CI tests Freddy Rolland: Verified -- To view, visit https://gerrit.ovirt.org/77241 To unsubscribe, visit https://gerrit.ovirt.org/settings Gerrit-MessageType: merged Gerrit-Change-Id: Iffc45d2ef28b65894504e49f6e966c81c4a16c3f Gerrit-PatchSet: 1 Gerrit-Project: ovirt-engine Gerrit-Branch: ovirt-engine-4.1 Gerrit-Owner: Freddy Rolland <frolland(a)redhat.com&gt; Gerrit-Reviewer: Allon Mureinik <amureini(a)redhat.com&gt; Gerrit-Reviewer: Fred Rolland <frolland(a)redhat.com&gt; Gerrit-Reviewer: Freddy Rolland <frolland(a)redhat.com&gt; Gerrit-Reviewer: Jenkins CI Gerrit-Reviewer: Tal Nisan <tnisan(a)redhat.com&gt; Gerrit-Reviewer: gerrit-hooks <automation(a)ovirt.org&gt;