Barrier Execution Mode
Barrier Execution Mode is…FIXME
|The barrier execution mode is experimental and it only handles limited scenarios.|
In case of a task failure, instead of only restarting the failed task, Spark will abort the entire stage and re-launch all tasks for this stage.
mapPartitions[S: ClassTag]( f: Iterator[T] => Iterator[S], preservesPartitioning: Boolean = false): RDD[S]
Taskhas a isBarrier flag that says whether this task belongs to a barrier stage (default:
Spark must launch all the tasks at the same time for a barrier stage.
An RDD is in a barrier stage, if at least one of its parent RDD(s), or itself, are mapped from an
Barrier Stage is a stage that…FIXME