title: Map and Reduce task memory settings in Hadoop YARN
body: <p>Does the max memory for Reduce task need to more than the Map task in a MapReduce application on YARN? Like below...</p>
  
  <pre><code>mapreduce.map.memory.mb = 7
  mapreduce.reduce.memory.mb = 14
  mapreduce.map.java.opts = 0.8 * 7 = 5,6
  mapreduce.reduce.java.opts = 0.8 * 2 * 7 = 11,2
  </code></pre>