I am seeing the following exception in my Spark Cluster every few days in production.
2016-03-12 05:30:00,541 - WARN TaskSetManager - Lost task 0.0 in stage 12528.0 (TID 18792, ip-1X-1XX-1-1XX.us <http://ip-10-180-1-188.us/>-west-1.compute.internal ): java.lang.NullPointerException at org.apache.spark.util.collection.ExternalSorter.insertAll(ExternalSorter.scala:192) at org.apache.spark.shuffle.sort.SortShuffleWriter.write(SortShuffleWriter.scala:64) at org.apache.spark.scheduler.ShuffleMapTask.runTask(ShuffleMapTask.scala:73) at org.apache.spark.scheduler.ShuffleMapTask.runTask(ShuffleMapTask.scala:41) at org.apache.spark.scheduler.Task.run(Task.scala:89) at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:213) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:745) I have debugged in local machine but haven’t been able to pin point the cause of the error. Anyone knows why this might occur? Any suggestions? Thanks, Saurabh