title: is there a limit to the number of threads that ruby can run at once?
body: <p>If not whats the maximum while still remaining efficient?  </p>
  
  <p>I'm creating 14 threads, each of which opens a list of URLs(about 500) creates a new thread for each one, which then downloads it, and adds it to a MySQL db. The MySQL pool size is set to 50.</p>
  
  <p>This is a rake task in RoR.</p>
  
  <p>Would this work better using <code>Kernal#fork</code> or some other method?</p>