title: Implementing user activity in symfony 2
body: <p>What's the best way to implement user activity in symfony 2 ?</p>
  
  <p>And how to do it ? </p>
  
  <p>I know there is the event system of symfony 2. Maybe I should trigger an event ?</p>
  
  <p>And is it wise to update on every page request or are there other (better) ways to update user activity ?</p>