Note : Use Accumulator only in action to get correct values. Do not use Accumulator in Transformation ; Use it only for debugging purpose in Transformation
scala> val input = sc.parallelize(List(1, 2, 3, 4, 5,
| 6, 7, 8, 9, 10,
| 11, 12, 13, 14, 15
| ))
input: org.apache.spark.rdd.RDD[Int] = ParallelCollectionRDD[0] at parallelize at <console>:27
scala> println("No of partitions -> " + input.partitions.size)
No of partitions -> 8
scala> val myAccum = sc.accumulator(0, "My Accumulator")
myAccum: org.apache.spark.Accumulator[Int] = 0
scala> // Used inside an action
scala> input.foreach{ x =>
| //Thread.sleep(50000)
| myAccum += 1
| }
scala> println("myAccum -> " + myAccum.value)
myAccum -> 15
c15 > a15