In storm, you can control the number of thread with the setSpout/setBolt, and how to do the same with Spark Streaming?
e.g.
val lines = ssc.socketTextStream(args(1), args(2).toInt)
val words = lines.flatMap(_.split(" "))
val wordCounts = words.map(x => (x, 1)).reduceByKey(_ + _)
wordCounts.print()
ssc.start()
Sound like I cannot tell Spark to tell how many thread to be used with
`flatMap` and how many thread to be used with `map` etc, right?
