Queue slots not released after Workflow canceled by last Task inside Workflow.

Document ID : KB000087346
Last Modified Date : 14/04/2018
Show Technical Document Details
Error Message :

Queue slots are not released after a Workflow has been canceled by the last Task inside a Workflow.

In order for this issue to occur when a Workflow (i.e. WF1) is submitted into a queue and one of the internal tasks within the workflow aborts, WF1 will remain in the queue in a status of BLOCKED.  If a second Workflow (i.e. WF2) is submitted in the same queue that workflow will remain in a status of Waiting for Predecessor.  Because the Job Queue is limited to a maximum of 1 Job execution at a time, the workflows are behaving as expected.

If the failed job within WF1 is executed again and it ends successfully, WF1 will continue and end in a status of ENDED_OK.  The job queues slot is now released and WF2 should start. Instead, WF2 remains indefinitely in a status of Waiting for Predecessor.

OS: Windows Server 2012
OS Version: N/A
Cause type:
Root Cause: Queue-slots are not released after a workflow has been canceled by the last task inside the workflow.
Update to a fix version listed below or a newer version if available.

Fix Status: Released

Fix Version(s):
Automation Engine 12.1.0 - Available
Automation Engine 12.0.3 - Available
Additional Information:
Workaround :
Restart the job queue to release the waiting Workflow.