Want to optimize the performance of your code? Ben Evans and Chris Newland wrap up their three-part series about using JITWatch to understand the just-in-time (JIT) compilation techniques used by the dynamic compiler in Oracle’s Java HotSpot VM. JITWatch is a free, open source tool developed by Newland that analyzes the complex compilation log file output generated by Java HotSpot VM. Among other things, it can help you visualize and understand the optimization decisions made by Java HotSpot VM.
describes how to use JITWatch to see the effects that even small source code changes can have on Java HotSpot VM switches. Learn about Sandbox and VM switches features. Sandbox will let you edit code and then compile, execute, and analyze the Java HotSpot VM JIT logs. The VM switches are used to control JIT compilation.
In the September/October edition of Java Magazine Ben and Chris wrote part 2, which focuses on how to examine JIT logs to see what the JIT compiler is doing (and why). Part 1
provides a primer on JIT compilation.