title: Coldfusion 10 slower when using Java 1.7 compared to 1.6
body: <p>I have a webservice running on <code>Coldfusion 10 64bit</code>. While investigating a memory leak I went to upgrade the JRE from 1.6 to 1.7 but noticed a significant performance hit. I had created a simple test webservice which on JRE 1.6 I could run easily at 5000 requests per minute as soon as I changed the JRE to 1.7 though this rate drops too 2000 or less per minute. Does anyone know of tuning settings or something I am missing. </p>
  
  <p>The preference is to use <code>JRE 1.7</code> as it appears to have fixed the memory leak issue I was having.</p>
  
  <ul>
  <li><p>Running Server JRE: java version "1.7.0_51" Java(TM) SE Runtime Environment (build 1.7.0_51-b13) Java HotSpot(TM) 64-Bit Server VM (build 24.51-b03, mixed mode) </p></li>
  <li><p>Garbage Collection in JVM settings: <code>-XX:+UseParallelGC</code></p></li>
  <li><p>Changed Garbage Collection to : <code>-XX:+UseG1GC</code> this made no difference.</p></li>
  </ul>
  
  <p>Followed <a href="http://www.cfwhisperer.com/post.cfm/coldfusion-10-enhanced-performance-settings" rel="noreferrer">the recommendations from here</a> with no increase in performance. Will review with jvisualvm and post my findings.</p>
  
  <p><strong>Update:</strong> 
  Java 7 has <a href="http://docs.oracle.com/javase/7/docs/technotes/guides/lang/cl-mt.html" rel="noreferrer">changed the way it deals with synchronizing class loaders</a> and it looks like this may be the cause of the slowdown.</p>
  
  <p><strong>Update</strong>
  Adobe has acknowledged the bug and is looking to fix it. <a href="https://bugbase.adobe.com/index.cfm?event=bug&amp;id=3711982" rel="noreferrer">Adobe bug base record.</a></p>