title: -XX:+UseCompressedOops does not work in Eclipse
body: <p>My Java (64bit) version information is as below:</p>
  
  <pre><code>D:\workspace\s3-jerome\Voice\nlp&gt;java -version
  java version "1.7.0_09"
  Java(TM) SE Runtime Environment (build 1.7.0_09-b05)
  Java HotSpot(TM) 64-Bit Server VM (build 23.5-b02, mixed mode)
  </code></pre>
  
  <p>My application has a lot of instances, therefore it consumes plenty of memory if each reference occupies 8 bytes. So I want to use the -XX:+UseCompressedOops to force JVM to compress OOP. In eclipse, I have added -XX:+UseCompressedOops in the VM Arguments in run configuration.</p>
  
  <p>But when I profile my program with VisualVM 1.3.7, I still get the result that size of each reference is 8 bytes.  The instance size of the following class is still 32!</p>
  
  <pre><code>public class AcLinkedList&lt;E&gt; {
      private E element;
      private AcLinkedList&lt;E&gt; next;
  
      public AcLinkedList(E element) {
         this.element = element;
         next = null;
      };
  
      .......
  }
  </code></pre>
  
  <p>Anybody knows where is the problem?</p>