title: How to change memory per node for apache spark worker
body: <p>I am configuring an Apache Spark cluster.</p>
  
  <p>When I run the cluster with 1 master and 3 slaves, I see this on the master monitor page:</p>
  
  <pre><code>Memory
  2.0 GB (512.0 MB Used)
  2.0 GB (512.0 MB Used)
  6.0 GB (512.0 MB Used)
  </code></pre>
  
  <p>I want to increase the used memory for the workers but I could not find the right config for this. I have changed <strong>spark-env.sh</strong> as below:</p>
  
  <pre><code>export SPARK_WORKER_MEMORY=6g
  export SPARK_MEM=6g
  export SPARK_DAEMON_MEMORY=6g
  export SPARK_JAVA_OPTS="-Dspark.executor.memory=6g"
  export JAVA_OPTS="-Xms6G -Xmx6G"
  </code></pre>
  
  <p>But the used memory is still the same. What should I do to change used memory?</p>