title: How are key/value pairs distributed in Hadoop when using multiple reducers?
body: <p>Suppose I have a job which has a number of mappers and more than one reduce task. The key type the mapper outputs is WritableComparable. I.e., for the word count example, let's say I have the string:</p>
  
  <p>"foo foo bar foo bletch quux bar"</p>
  
  <p>When using the words as a key, is "foo" always distributed to the same reduce or is it possible that more than one reducer receives a "foo"?</p>