This issue looks like it's caused by the DB lock being released before the engine memory lock, there was a similar race with the LSM test a few months back. I'll apply the same fix for the snapshot_cold_merge.
.

On Tue, Mar 27, 2018 at 10:03 PM, Benny Zlotnik <bzlotnik@redhat.com> wrote:

Looking into this

On Tue, Mar 27, 2018 at 6:45 PM, Dafna Ron <dron@redhat.com> wrote:

Hi,

We have a failure on 004_basic_sanity.disk_operations. the reported change seems to me to be connected to the failure.

Link and headline of suspected patches:

core: introduce CreateSnapshotForVm - https://gerrit.ovirt.org/#/c/87671/

Link to Job:

http://jenkins.ovirt.org/job/ovirt-master_change-queue-tester/6564/

Link to all logs:

http://jenkins.ovirt.org/job/ovirt-master_change-queue-tester/6564/artifact/exported-artifacts/basic-suit-master-el7/test_logs/basic-suite-master/post-004_basic_sanity.py/

(Relevant) error snippet from the log:

<error>

2018-03-27 11:30:16,167-04 WARN  [org.ovirt.engine.core.bll.snapshots.CreateSnapshotForVmCommand] (default task-11) [9f713a3d-82a9-4db8-8207-bb69a0a2c550] Validation of action 'CreateSnapshotForVm' failed for user admin@internal-authz. Re
asons: VAR__ACTION__CREATE,VAR__TYPE__SNAPSHOT,ACTION_TYPE_FAILED_SNAPSHOT_IS_BEING_TAKEN_FOR_VM,$VmName vm1
2018-03-27 11:30:16,176-04 DEBUG [org.ovirt.engine.core.common.di.interceptor.DebugLoggingInterceptor] (default task-11) [9f713a3d-82a9-4db8-8207-bb69a0a2c550] method: runAction, params: [CreateSnapshotForVm, CreateSnapshotForVmParameters
:{commandId='d8bfdb0e-5ae4-4fed-8852-a0b29e377708', user='null', commandType='Unknown', vmId='65e7fea5-8b7d-4281-bd0d-6a84de207a00'}], timeElapsed: 57ms
2018-03-27 11:30:16,186-04 ERROR [org.ovirt.engine.api.restapi.resource.AbstractBackendResource] (default task-11) [] Operation Failed: [Cannot create Snapshot. Snapshot is currently being created for VM vm1.]
2018-03-27 11:30:16,820-04 INFO  [org.ovirt.engine.core.bll.SerialChildCommandsExecutionCallback] (EE-ManagedThreadFactory-engineScheduled-Thread-100) [16c08ce6-9a73-489f-a1f2-56e21699f14a] Command 'CopyImageGroupVolumesData' (id: '4c4023
b4-21e8-4a98-8ac3-aba51967d160') waiting on child command id: '3d96b933-6e3b-4838-94bc-db3ff0cadcdc' type:'CopyData' to complete
2018-03-27 11:30:16,833-04 DEBUG [org.ovirt.engine.core.common.di.interceptor.DebugLoggingInterceptor] (EE-ManagedThreadFactory-engineScheduled-Thread-100) [16c08ce6-9a73-489f-a1f2-56e21699f14a] method: get, params: [a85992e9-40b8-4c80-9c
93-3bf767f6efa4], timeElapsed: 8ms

</error>