title: HTML Web Application Notification System
body: <p>I'm using Play Framework 2.3 (Java) and MySQL. </p>
  
  <p>I'm building a notification system that reads from a "notifications" table in MySQL. </p>
  
  <p>I've tried using AJAX polling where a request is sent asynchronously every 30 seconds, the table is read and if any new notifications exist, are sent via JSON back to the client. However, the performance is concerning, especially with many concurrent users. </p>
  
  <p>What's the best way to build such a system? Are there any particular Java libraries that would work well for this?</p>
  
  <p>Thanks in advance.</p>