JobListener
Spark subscribes for job completion or failure events (after submitting a job to DAGScheduler) using JobListener trait.
The following are the job listeners used:
-
JobWaiter waits until DAGScheduler completes a job and passes the results of tasks to a
resultHandlerfunction. -
ApproximateActionListener…FIXME
An instance of JobListener is used in the following places:
-
In
ActiveJobas a listener to notify if tasks in this job finish or the job fails. -
In
JobSubmitted
JobListener Contract
JobListener is a private[spark] contract with the following two methods:
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private[spark] trait JobListener { def taskSucceeded(index: Int, result: Any) def jobFailed(exception: Exception) } |
A JobListener object is notified each time a task succeeds (by taskSucceeded) and when the whole job fails (by jobFailed).
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