JBoss profiling shows CPU increases using Sun JDK 1.6 vs. JRockit JDK 1.6

Issue

• We are preparing a migration from WebLogic to JBoss, however, when running comparative stress tests on the following environment stacks:

1. SUSE Linux Enterprise Server 10 (x86_64) VERSION = 10 PATCHLEVEL = 1
   JBoss EAP 4.3
   SUN JDK 1.6.0_18
2. SUSE Linux Enterprise Server 10 (x86_64) VERSION = 10 PATCHLEVEL = 1
   JBoss EAP 4.3
   BEA JRockit JDK 1.6 (jrmc-3.1.2-1.6.0)

• We find that running test and profiling the two different stacks using the same load and webpage (servlet) generates 73% higher CPU utilization using stack #1 compared with the alternative stack #2.
• When profiling the application on the current stack using the same load and webpage (servlet) we can see the majority of CPU time is spent on native calls such as:
  java-lang.System.arraycopy()
  java.lang.String.intern()
  java.lang.ClassLoader.getPackage()