Spark 源码分析 -- Task
Task是介于DAGScheduler和TaskScheduler中间的接口 在DAGScheduler, 需要把DAG中的每个stage的每个partitions封装成task 最终把taskset提交给TaskScheduler /** * A task to execute on a worker node. */ private[spark] abstract class Task[T](val stageId: Int) extends Serializable { def run(attemptId: Long): T //Task的核心函数 def preferredLocations: Seq[TaskLocation] = Nil //Spark关注locality,可以选择该task运行的location var epoch: Long = -1 // Map output tracker epoch. Will be set by TaskScheduler. var metrics: Option[TaskMetrics] = None } TaskCont...
