What Is Micro Benchmark?

This section describes what is Java micro benchmark and general guidelines on writing micro benchmark programs.

What Is Micro Benchmark? Micro benchmark is a benchmark designed to measure the performance of a very small and specific piece of code.

One good example of Java Micro Benchmark programs is the Java Microbenchmark Applet maintained by Jonathan Hardwick at http://www.cs.cmu.edu/~jch/java/microbench.html. It is designed to measure the performance of Java basic operations like:

If you want to write your own micro benchmark programs, you need to consider:

Table of Contents

 About This Book

 JVM (Java Virtual Machine) Specification

 Java HotSpot VM - JVM by Oracle/Sun

 java.lang.Runtime Class - The JVM Instance

 java.lang.System Class - The Operating System

 ClassLoader Class - Class Loaders

 Class Class - Class Reflections

 JVM Runtime Data Areas

 JVM Stack, Frame and Stack Overflow

 Thread Testing Program and Result

 CPU Impact of Multi-Thread Applications

 I/O Impact of Multi-Thread Applications

 CDS (Class Data Sharing)

Micro Benchmark Runner and JVM Options

What Is Micro Benchmark?

 BenchmarkRunner.java - Benchmark Runner Program

 emptyLoop() - The Empty Loop Test Method

 "-XX:+PrintCompilation" - Watching JIT Compilation Logs

 "-XX:+PrintGC" - Watching GC (Garbage Collection) Logs

 "-Xms" and "-Xmx" - Avoiding GC with Large Memory Size

 Benchmark Affected by Other Running Applications

 "-Xint" - Running in Interpreted-Only Mode

 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

 OpenJ9 by Eclipse Foundation

 JRockit JVM 28.2.7 by Oracle Corporation

 Archived Tutorials

 References

 Full Version in PDF/EPUB