Github user rdblue commented on a diff in the pull request:
https://github.com/apache/spark/pull/11242#discussion_r62238592
--- Diff: core/src/main/scala/org/apache/spark/rdd/UnionRDD.scala ---
@@ -62,8 +64,22 @@ class UnionRDD[T: ClassTag](
var rdds: Seq[RDD[T]])
extends RDD[T](sc, Nil) { // Nil since we implement getDependencies
+ // visible for testing
+ private[spark] val isPartitionListingParallel: Boolean =
+ rdds.length > conf.getInt("spark.rdd.parallelListingThreshold", 10)
+
+ @transient private lazy val partitionEvalTaskSupport =
+ new ForkJoinTaskSupport(new ForkJoinPool(8))
+
override def getPartitions: Array[Partition] = {
- val array = new Array[Partition](rdds.map(_.partitions.length).sum)
+ val parRDDs = if (isPartitionListingParallel) {
+ val parArray = rdds.par
+ parArray.tasksupport = partitionEvalTaskSupport
+ parArray
+ } else {
+ rdds
+ }
+ val array = new Array[Partition](parRDDs.map(_.partitions.length).sum)
--- End diff --
I just pushed a fix with what you suggested. It's really strange to me that
the thread pool changes. Seems like the new parallel collection should use its
parent's task support. Good catch, and thanks for reviewing!
---
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 [email protected] or file a JIRA ticket
with INFRA.
---
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
