GitHub user seyfe opened a pull request: https://github.com/apache/spark/pull/15425
[SPARK-17816] [Core] [Branch-2.0] Fix ConcurrentModificationException issue in BlockStatusesAccumulator ## What changes were proposed in this pull request? Replaced `BlockStatusesAccumulator` with `CollectionAccumulator` which is thread safe and few more cleanups. ## How was this patch tested? Tested in master branch and cherry-picked. You can merge this pull request into a Git repository by running: $ git pull https://github.com/seyfe/spark race_cond_jsonprotocal_branch-2.0 Alternatively you can review and apply these changes as the patch at: https://github.com/apache/spark/pull/15425.patch To close this pull request, make a commit to your master/trunk branch with (at least) the following in the commit message: This closes #15425 ---- commit 678ee6b1d6308a81a5c2d83a196144f29c80434b Author: Ergin Seyfe <ese...@fb.com> Date: 2016-10-11T03:41:31Z [SPARK-17816][CORE] Fix ConcurrentModificationException issue in BlockStatusesAccumulator Change the BlockStatusesAccumulator to return immutable object when value method is called. Existing tests plus I verified this change by running a pipeline which consistently repro this issue. This is the stack trace for this exception: ` java.util.ConcurrentModificationException at java.util.ArrayList$Itr.checkForComodification(ArrayList.java:901) at java.util.ArrayList$Itr.next(ArrayList.java:851) at scala.collection.convert.Wrappers$JIteratorWrapper.next(Wrappers.scala:43) at scala.collection.Iterator$class.foreach(Iterator.scala:893) at scala.collection.AbstractIterator.foreach(Iterator.scala:1336) at scala.collection.IterableLike$class.foreach(IterableLike.scala:72) at scala.collection.AbstractIterable.foreach(Iterable.scala:54) at scala.collection.generic.Growable$class.$plus$plus$eq(Growable.scala:59) at scala.collection.mutable.ListBuffer.$plus$plus$eq(ListBuffer.scala:183) at scala.collection.mutable.ListBuffer.$plus$plus$eq(ListBuffer.scala:45) at scala.collection.TraversableLike$class.to(TraversableLike.scala:590) at scala.collection.AbstractTraversable.to(Traversable.scala:104) at scala.collection.TraversableOnce$class.toList(TraversableOnce.scala:294) at scala.collection.AbstractTraversable.toList(Traversable.scala:104) at org.apache.spark.util.JsonProtocol$.accumValueToJson(JsonProtocol.scala:314) at org.apache.spark.util.JsonProtocol$$anonfun$accumulableInfoToJson$5.apply(JsonProtocol.scala:291) at org.apache.spark.util.JsonProtocol$$anonfun$accumulableInfoToJson$5.apply(JsonProtocol.scala:291) at scala.Option.map(Option.scala:146) at org.apache.spark.util.JsonProtocol$.accumulableInfoToJson(JsonProtocol.scala:291) at org.apache.spark.util.JsonProtocol$$anonfun$taskInfoToJson$12.apply(JsonProtocol.scala:283) at org.apache.spark.util.JsonProtocol$$anonfun$taskInfoToJson$12.apply(JsonProtocol.scala:283) at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:234) at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:234) at scala.collection.immutable.List.foreach(List.scala:381) at scala.collection.generic.TraversableForwarder$class.foreach(TraversableForwarder.scala:35) at scala.collection.mutable.ListBuffer.foreach(ListBuffer.scala:45) at scala.collection.TraversableLike$class.map(TraversableLike.scala:234) at scala.collection.AbstractTraversable.map(Traversable.scala:104) at org.apache.spark.util.JsonProtocol$.taskInfoToJson(JsonProtocol.scala:283) at org.apache.spark.util.JsonProtocol$.taskEndToJson(JsonProtocol.scala:145) at org.apache.spark.util.JsonProtocol$.sparkEventToJson(JsonProtocol.scala:76) ` Author: Ergin Seyfe <ese...@fb.com> Closes #15371 from seyfe/race_cond_jsonprotocal. ---- --- If your project is set up for it, you can reply to this email and have your reply appear on GitHub as well. If your project does not have this feature enabled and wishes so, or if the feature is enabled but not working, please contact infrastructure at infrastruct...@apache.org or file a JIRA ticket with INFRA. --- --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org