title: What does the MAVEN_OPTS environment variable do?
body: <p>For example:-</p>
  
  <pre><code>MAVEN_OPTS=" -Xms512m -Xmx1024m -XX:MaxPermSize=1024m"
  export MAVEN_OPTS
  </code></pre>
  
  <p>What does <code>"-Xms512m -Xmx1024m -XX:MaxPermSize=1024m"</code> mean?</p>