title: Java 8 stream parallelism: set number of threads to use?
body: <p>Reading Java 8's streaming API for parallelism:
  <a href="https://docs.oracle.com/javase/tutorial/collections/streams/parallelism.html" rel="nofollow">https://docs.oracle.com/javase/tutorial/collections/streams/parallelism.html</a></p>
  
  <p>It's not clear how to tune the number of threads to use when using this streaming API's parallelism?</p>
  
  <p>Plan to run this on a very specific type of machine and a consistent data types, so I was thinking I can benchmark it over a set of different settings then use the best number of threads.</p>