Java Performance Tuning
A big part of tuning the performance of a Java application server is tuning the Java VM in which the application server runs.A big part of tuning the performance of a Java application server is tuning the Java VM in which the application server runs. On some platforms, organizations will have a choice of Java virtual machines. Sun Microsystems Inc. and IBM both produce their own VMs for several operating systems, and other platform vendors also make a Java VM tuned for their platforms. In these cases, organizations can choose the VM that handles their workloads the best. In our setup (using BEA Systems Inc.s WebLogic 6.1 running on Windows 2000 Advanced Server), we ran tests using Java 1.3 VMs from Sun and IBM.
We found the IBM Java VM more stable (we had three crashes of the Sun VM during three weeks of testing and none with the IBM VM while we were using it) but also found the IBM VM took up about 20 percent more CPU on the same workload as the Sun VM (when the Sun VM was in its most optimized state).