[ 
https://issues.apache.org/jira/browse/SPARK-23626?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Ajith S reopened SPARK-23626:
-----------------------------

Old PR was closed due to inactivity. Reopening with a new PR and hence to 
conclude

>  DAGScheduler blocked due to JobSubmitted event
> -----------------------------------------------
>
>                 Key: SPARK-23626
>                 URL: https://issues.apache.org/jira/browse/SPARK-23626
>             Project: Spark
>          Issue Type: Bug
>          Components: Scheduler
>    Affects Versions: 2.2.1, 2.3.3, 2.4.3, 3.0.0
>            Reporter: Ajith S
>            Priority: Major
>
> DAGScheduler becomes a bottleneck in cluster when multiple JobSubmitted 
> events has to be processed as DAGSchedulerEventProcessLoop is single threaded 
> and it will block other tasks in queue like TaskCompletion.
> The JobSubmitted event is time consuming depending on the nature of the job 
> (Example: calculating parent stage dependencies, shuffle dependencies, 
> partitions) and thus it blocks all the events to be processed.
>  
> I see multiple JIRA referring to this behavior
> https://issues.apache.org/jira/browse/SPARK-2647
> https://issues.apache.org/jira/browse/SPARK-4961
>  
> Similarly in my cluster some jobs partition calculation is time consuming 
> (Similar to stack at SPARK-2647) hence it slows down the spark 
> DAGSchedulerEventProcessLoop which results in user jobs to slowdown, even if 
> its tasks are finished within seconds, as TaskCompletion Events are processed 
> at a slower rate due to blockage.



--
This message was sent by Atlassian Jira
(v8.3.4#803005)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org
For additional commands, e-mail: issues-h...@spark.apache.org

Reply via email to