The Looker Scheduler is very robust — however, rarely, scheduled jobs can fail in the scheduled job queue without the job having been closed.
Starting in Looker 7.2, the Scheduler monitors the scheduled job queue for jobs that have been enqueued for an hour or more while more recent jobs have been successfully dequeuing. If this occurs, the scheduled job is closed and reported as failed on the Schedule History page in Looker's Admin section, returning one of the following messages:
Job is no longer processing @ <state>(where
Job was expected to dequeue by @ <time>
If you see one of these messages, your scheduled job will execute the next time it is scheduled to run.
To view all failed jobs on the Schedule History page:
From Looker's Admin menu, select Schedule History.
Click the Failed button to filter the list of scheduled jobs to show only the jobs that failed.
The Message column lists the reasons each scheduled job failed.