JVM Tutorials - Herong's Tutorial Examples

∟Micro Benchmark Tests on "float" and "double" Operations

This chapter provides tutorial notes and example codes on micro benchmark tests on 'float' and 'double' data type operations using HotSpot JVM with and without JIT compilation. Topics include empty loop, assignment loop, add operation, multiplication operation and division operation.

Benchmark Test Methods for "float" Operation

"float" Operations without JIT Compilation

"float" Operations with JIT Compilation

Benchmark Test Methods for "double" Operation

"double" Operations without JIT Compilation

"double" Operations with JIT Compilation

Performance Improvements of JIT Compilation

Conclusions:

• My computer configuration: Intel Core 2 CPU of T7200 @ 2.00GHz with memory 997 MHz and 1.00 GB.
• HotSpot JIT compilation reduces execution time by about 10 to 20 times on some simple "float" or "double" operations.
• In JIT compilation mode, "double" operations are not must slower than "float" operations.
• A division operation is much slower than an add, or multiply operation!

Table of Contents

 About This Book

 Download and Install Java SE 1.6 Update 2

 java.lang.Runtime Class - The JVM Instance

 java.lang.System Class - The Operating System

 ClassLoader Class - Class Loaders

 Class Class - Class Reflections

 Sun's JVM - Java HotSpot VM

 JRockit JVM 7.0 by BEA Systems

 JRockit JVM 8.0 by BEA Systems

 Memory Management Rules and Tests

 Garbage Collection Tests

 Stack Overflow Tests

 Thread Testing Program and Result

 StringBuffer Testing Program and Result

 CDS (Class Data Sharing)

 Micro Benchmark Runner and JVM Options

 Micro Benchmark Tests on "int" Operations

 Micro Benchmark Tests on "long" Operations

 Micro Benchmark Tests in JIT Compilation Mode

►Micro Benchmark Tests on "float" and "double" Operations

 References

 PDF Printing Version