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TaskInfo

== [[TaskInfo]] TaskInfo

TaskInfo is information about a running task attempt inside a scheduler:TaskSet.md[TaskSet].

TaskInfo is created when:

  • scheduler:TaskSetManager.md#resourceOffer[TaskSetManager dequeues a task for execution (given resource offer)] (and records the task as running)

  • TaskUIData does dropInternalAndSQLAccumulables

  • JsonProtocol utility is used to spark-history-server:JsonProtocol.md#taskInfoFromJson[re-create a task details from JSON]

NOTE: Back then, at the commit 63051dd2bcc4bf09d413ff7cf89a37967edc33ba, when TaskInfo was first merged to Apache Spark on 07/06/12, TaskInfo was part of spark.scheduler.mesos package -- note "Mesos" in the name of the package that shows how much Spark and Mesos influenced each other at that time.

[[internal-registries]] .TaskInfo's Internal Registries and Counters [cols="1,2",options="header",width="100%"] |=== | Name | Description

| [[finishTime]] finishTime | Time when TaskInfo was <>.

Used when...FIXME |===

=== [[creating-instance]] Creating TaskInfo Instance

TaskInfo takes the following when created:

  • [[taskId]] Task ID
  • [[index]] Index of the task within its scheduler:TaskSet.md[TaskSet] that may not necessarily be the same as the ID of the RDD partition that the task is computing.
  • [[attemptNumber]] Task attempt ID
  • [[launchTime]] Time when the task was dequeued for execution
  • [[executorId]] Executor that has been offered (as a resource) to run the task
  • [[host]] Host of the <>
  • [[taskLocality]] scheduler:TaskSchedulerImpl.md#TaskLocality[TaskLocality], i.e. locality preference of the task
  • [[speculative]] Flag whether a task is speculative or not

TaskInfo initializes the <>.

=== [[markFinished]] Marking Task As Finished (Successfully or Not) -- markFinished Method

[source, scala]

markFinished(state: TaskState, time: Long = System.currentTimeMillis): Unit

markFinished records the input time as <>.

markFinished marks TaskInfo as <> when the input state is FAILED or <> for state being KILLED.

NOTE: markFinished is used when TaskSetManager is notified that a task has finished scheduler:TaskSetManager.md#handleSuccessfulTask[successfully] or scheduler:TaskSetManager.md#handleFailedTask[failed].


Last update: 2020-10-06