title: Spark Shell stuck in YARN Accepted state
body: <p>Running Spark 1.3.1 on Yarn and EMR.  When I run the spark-shell everything looks normal until I start seeing messages like <code>INFO yarn.Client: Application report for application_1439330624449_1561 (state: ACCEPTED)</code>.  These messages are generated endlessly, once per second.  Meanwhile, I am unable to use the Spark shell.  </p>
  
  <p>I don't understand why this is happening.  </p>