title: Check status of Celery worker
body: <p>I have a project that uses Celery.  I am periodically running into a scenario where my requests are making it to Celery but the tasks aren't being handed off to the workers, but rather the server is just returning a 500 error.</p>
  
  <p>When I restart Celery it starts working again.  I am only guessing that the worker is hanging which makes it so there aren't anymore workers available.  If I startup another batch of workers the requests start working again (which supports my theory).</p>
  
  <p>Questions:</p>
  
  <ol>
  <li>I understand celery by default logs to stderr.  I am not seeing any errors, so I am hoping there is another celery log somewhere.  Where would that be?</li>
  <li>Is there any way to lookup the status of workers?  Are they available? Are they hung?</li>
  <li>Could it be anything else?</li>
  </ol>