title: What is Hashed Index?
body: <p>MongoDB 2.4 has a new feature that i see everyone around is talking about, so here is my question (sorry if they are simple):</p>
  
  <ul>
  <li>Does MongoDB manage them without specifying the shard key? or does the admin choose the key?</li>
  <li>Are there any risks of being in a Hostspot problem, or disk IO lags since there is the word Hash and hash is something random?</li>
  </ul>