Micro Benchmark Tests on "long" Operations

JVM Tutorials - Herong's Tutorial Examples

Dr. Herong Yang, Version 4.10

JVM Tutorials - Herong's Tutorial Examples

∟Micro Benchmark Tests on "long" Operations

This chapter provides tutorial notes and example codes on micro benchmark tests on 'long' data type operations. Topics include empty loop, assignment loop, add operation, multiplication operation and division operation.

"long" Empty Loop: 25 Nanoseconds per Step

"long" Assignment Only: 24 Nanoseconds per Step

"long" Shift and Assignment: 30 Nanoseconds per Step

"long" Add and Assignment: 34 Nanoseconds per Step

"long" Multiply and Assignment: 38 Nanoseconds per Step

"long" Division and Assignment: 53 Nanoseconds per Step

Performance Comparisons between "int" and "long"

Conclusions:

My computer configuration: Intel Core 2 CPU of T7200 @ 2.00GHz with memory 997 MHz and 1.00 GB.
A "long" empty loop runs 25 nanoseconds per step in interpreted-only mode.
A "long" assignment loop of x=i runs 24 nanoseconds per step in interpreted-only mode.
A "long" shift and assignment loop of x=i<<1 runs 30 nanoseconds per step in interpreted-only mode.
A "long" add and assignment loop of x=i+i runs 34 nanoseconds per step in interpreted-only mode.
A "long" multiplication and assignment loop of x=i*3 runs 38 nanoseconds per step in interpreted-only mode.
A "long" division and assignment loop of x=i/3 runs 53 nanoseconds per step in interpreted-only mode.

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