Workflow Completion

A workflow can shut down once all active tasks complete without spawning further downstream activity - i.e., when n=0 window empties out.

Scheduler Stall

A workflow has stalled if:

No tasks are waiting on unstatisfied external events, like clock triggers and xtriggers.
AND All activity has ceased.
AND The workflow has not run to completion.

A workflow which has stalled requires manual intervention to continue.

Stalls are caused by final status incomplete tasks and partially satisfied tasks.

These most often result from task failures that the workflow does not handle automatically by retries or optional branching.

A stalled scheduler stays alive for a configurable timeout period to allow you to intervene, e.g. by manually triggering an incomplete task after fixing the bug that caused it to fail.

If a stalled workflow does eventually shut down, on the stall timeout or by stop command, it will immediately stall again on restart to await manual intervention.

Warning

Look in the scheduler log to see which tasks caused a stall.