title: What is the meaning of the -XX:NewRatio and -XX:OldSize JVM flags?
body: <p>I am starting my java app with the following command line :</p>
  
  <pre><code>java -XX:+PrintCommandLineFlags -verbose:gc -XX:+PrintGCDetails \
       -XX:+UseConcMarkSweepGC -jar start.jar
  </code></pre>
  
  <p>The JVM enables the following options:</p>
  
  <pre><code>-XX:MaxNewSize=87244800 -XX:MaxTenuringThreshold=4 -XX:NewRatio=7
  -XX:NewSize=21811200 -XX:OldPLABSize=16 -XX:OldSize=65433600
  -XX:+PrintCommandLineFlags -XX:+PrintGC -XX:+PrintGCDetails
  -XX:+UseCompressedOops -XX:+UseConcMarkSweepGC -XX:+UseParNewGC
  </code></pre>
  
  <p>Can anyone explains me the meaning of NewRatio and OldSize ? In particular OldSize is the initial size of the tenured generation ?</p>