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https://issues.apache.org/jira/browse/SPARK-24909?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16565437#comment-16565437
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Thomas Graves commented on SPARK-24909:
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this is unfortunately not a straight forward fix, the DAGScheduler doesn't have
control over the fine grain things in the taskscheduler/tasksetmanager, so
undoing some of that is not possible with the existing api.
one possible thing would be to undo the change in SPARK-19263,
[https://github.com/apache/spark/commit/729ce3703257aa34c00c5c8253e6971faf6a0c8d]
and fix that another way as well
Still working on a fix, just making a few notes.
> Spark scheduler can hang when fetch failures, executor lost, task running on
> lost executor, and multiple stage attempts
> -----------------------------------------------------------------------------------------------------------------------
>
> Key: SPARK-24909
> URL: https://issues.apache.org/jira/browse/SPARK-24909
> Project: Spark
> Issue Type: Bug
> Components: Scheduler
> Affects Versions: 2.3.1
> Reporter: Thomas Graves
> Priority: Critical
>
> The DAGScheduler can hang if the executor was lost (due to fetch failure) and
> all the tasks in the tasks sets are marked as completed.
> ([https://github.com/apache/spark/blob/master/core/src/main/scala/org/apache/spark/scheduler/DAGScheduler.scala#L1265)]
> It never creates new task attempts in the task scheduler but the dag
> scheduler still has pendingPartitions.
> {code:java}
> 8/07/22 08:30:00 INFO scheduler.TaskSetManager: Starting task 55769.0 in
> stage 44.0 (TID 970752, host1.com, executor 33, partition 55769,
> PROCESS_LOCAL, 7874 bytes)
> 18/07/22 08:30:29 INFO scheduler.DAGScheduler: Marking ShuffleMapStage 44
> (repartition at Lift.scala:191) as failed due to a fetch failure from
> ShuffleMapStage 42 (map at foo.scala:27)
> 18/07/22 08:30:29 INFO scheduler.DAGScheduler: Resubmitting ShuffleMapStage
> 42 (map at foo.scala:27) and ShuffleMapStage 44 (repartition at
> bar.scala:191) due to fetch failure
> ....
> 18/07/22 08:30:56 INFO scheduler.DAGScheduler: Executor lost: 33 (epoch 18)
> 18/07/22 08:30:56 INFO schedulerDAGScheduler: Shuffle files lost for
> executor: 33 (epoch 18)
> 18/07/22 08:31:20 INFO scheduler.DAGScheduler: Submitting ShuffleMapStage 44
> (MapPartitionsRDD[70] at repartition at bar.scala:191), which has no missing
> parents
> 18/07/22 08:31:21 INFO cluster.YarnClusterScheduler: Adding task set 44.1
> with 59955 tasks
> 18/07/22 08:31:41 INFO scheduler.TaskSetManager: Finished task 55769.0 in
> stage 44.0 (TID 970752) in 101505 ms on host1.com (executor 33) (15081/73320)
> 8/07/22 08:31:41 INFO scheduler.DAGScheduler: Ignoring possibly bogus
> ShuffleMapTask(44, 55769) completion from executor 33{code}
>
>
> In the logs above you will see that task 55769.0 finished after the executor
> was lost and a new task set was started. The DAG scheduler says "Ignoring
> possibly bogus".. but in the TaskSetManager side it has marked those tasks as
> completed for all stage attempts. The DAGScheduler gets hung here. I did a
> heap dump on the process and can see that 55769 is still in the DAGScheduler
> pendingPartitions list but the tasksetmanagers are all complete
>
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