Andy Sloane created SPARK-13631: ----------------------------------- Summary: getPreferredLocations race condition in spark 1.6.0? Key: SPARK-13631 URL: https://issues.apache.org/jira/browse/SPARK-13631 Project: Spark Issue Type: Bug Components: Scheduler Affects Versions: 1.6.0 Reporter: Andy Sloane
We are seeing something that looks a lot like a regression from spark 1.2. When we run jobs with multiple threads, we have a crash somewhere inside getPreferredLocations, as was fixed in SPARK-4454. Except now it's inside org.apache.spark.MapOutputTrackerMaster.getLocationsWithLargestOutputs instead of DAGScheduler directly. I tried Spark 1.2 post-SPARK-4454 (before this patch it's only slightly flaky), 1.4.1, and 1.5.2 and all are fine. 1.6.0 immediately crashes on our threaded test case, though once in a while it passes. The stack trace is huge, but starts like this: Caused by: java.lang.NullPointerException: null at org.apache.spark.MapOutputTrackerMaster.getLocationsWithLargestOutputs(MapOutputTracker.scala:406) at org.apache.spark.MapOutputTrackerMaster.getPreferredLocationsForShuffle(MapOutputTracker.scala:366) at org.apache.spark.rdd.ShuffledRDD.getPreferredLocations(ShuffledRDD.scala:92) at org.apache.spark.rdd.RDD$$anonfun$preferredLocations$2.apply(RDD.scala:257) at org.apache.spark.rdd.RDD$$anonfun$preferredLocations$2.apply(RDD.scala:257) at scala.Option.getOrElse(Option.scala:120) at org.apache.spark.rdd.RDD.preferredLocations(RDD.scala:256) at org.apache.spark.scheduler.DAGScheduler.org$apache$spark$scheduler$DAGScheduler$$getPreferredLocsInternal(DAGScheduler.scala:1545) The full trace is available here: https://gist.github.com/andy256/97611f19924bbf65cf49 -- This message was sent by Atlassian JIRA (v6.3.4#6332) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org