Why aren't my scala futures more efficient?

Question

I\'m running this scala code on a 32-bit quad-core Core2 system:

def job(i:Int,s:Int):Long = {
  val r=(i to 500000000 by s).map(_.toLong).foldLeft(0L)(_+_)
  pr         


        

Answer 1

Try

(i to 500000000 by s).view.map(_.toLong).foldLeft(0L)(_+_)

The application of view is supposed to (as I understood id) to avoid repeated iteration and object creation by providing simple wrappers.

Note also that you can use reduceLeft(_+_) instead of fold.