scala> val a = sc.parallelize(Array(1,2,3)).distinct
a: org.apache.spark.rdd.RDD[Int] = MapPartitionsRDD[3] at distinct at <console>:24
scala> a.toDebugString
res0: String =
(16) MapPartitionsRDD[3] at distinct at <console>:24 []
| ShuffledRDD[2] at distinct at <console>:24 []
+-(16) MapPartitionsRDD[1] at distinct at <console>:24 []
| ParallelCollectionRDD[0] at parallelize at <console>:24 []
scala>
scala>
scala> val b = sc.parallelize(Array(1,2,3))
b: org.apache.spark.rdd.RDD[Int] = ParallelCollectionRDD[4] at parallelize at <console>:24
scala> b.toDebugString
res1: String = (16) ParallelCollectionRDD[4] at parallelize at <console>:24 []