Simple demonstration of speedup achievable with new parallel collection in Scala 2.9

gistfile1.scala

package com.ign

import scala.collection.mutable.ArrayBuffer

object Main extends App {	
	var wordList = ArrayBuffer[String]()
	val size = 10000
	
	for(i <- 1 to size)
	  wordList += ("foo" + i)
	
	def processWord(x: String) = {
	  // pretend this is a computationally intensive task
	  // (simulated here by a 1ms sleep, giving each call a run time on the order of 1ms)
	  Thread.sleep(1)
	  x.length
	}

	
	def seqProcess() = {
	  var sum = 0
	  for(i <- wordList) {
	    sum += processWord(i)
	  }
	  
	  sum
	}
	
	def foldSeqProcess() = wordList.foldLeft(0)(_ + processWord(_))
	
	def mapSeqProcess() = wordList.map(processWord).sum
	
	def parProcess() = wordList.par.map(processWord).sum
	
	def timeProcessing(processor: (() => Int), name: String) {
		val start = System.currentTimeMillis()
		
		val lengthSum = processor()
		
		val elapsed = System.currentTimeMillis()-start
		
		System.out.println(name + ": " + lengthSum + ", " + elapsed + " ms elapsed")
	}
	
	timeProcessing(seqProcess, "Sequential")
	timeProcessing(foldSeqProcess, "Sequential (mapping)")
	timeProcessing(mapSeqProcess, "Sequential (folding)")
	timeProcessing(parProcess, "Parallel")
}