title: Are there any guidelines to follow when choosing number of processes with multiprocessing?
body: <p>I'm just getting my feet wet with multiprocessing(and its totally awesome!), but I was wondering if there was any guidelines to selecting number of processes?  Is it just based on number of cores on the server? Is it somehow based on the application your running(number of loops, how much cpu it uses,etc)? etc...how do I decide how many processes to spawn? Right now, I'm just guessing and add/removing processes but it would be great if there was some kind of guideline or best practice. </p>
  
  <p>Another question, I know what happens if I add too few(program is slooow) but what if I add 'too many'?</p>
  
  <p>Thanks!</p>