What Is HotSpot?
This section describes what is HotSpot - A Java VM (Virtual Machine) developed by Sun Microsystems.
What Is HotSpot?
Java HotSpot VM is developed by Sun Microsystems. It has key feature called adaptive
compiler that application code will be analyzed as it runs to detect performance
bottlenecks, or "hot spots". The Java HotSpot VM will then compile those hot spots
for a boost in performance.
There are two implementations of the Java HotSport VM:
- Java HotSpot Client VM
- Java HotSpot Server VM
The main differences of the two implementations are:
- The Client VM has been specially tuned to reduce application start-up time
and memory footprint, making it particularly well suited for client environments.
- The Server VM has been specially tuned to maximize peak operating speed.
It is intended for running long-running server applications, for which having the
fastest possible operating speed is generally more important than having the fastest
possible start-up time.
Both implementations of Java HotSpot VM are included inside the J2SDK installation
package. The next two sections will explain how to invoke them.
By the way, Java HotSpot VM source code is available at
Last update: 2014.
Table of Contents
About This Book
Downloading and Installing JDK 1.8.0 on Windows
Downloading and Installing JDK 1.7.0 on Windows
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
►What Is HotSpot?
Running Java HotSpot Client VM
Running Java HotSpot Server VM
VM Memory Usages on Windows Systems
JRockit JVM 28.2.7 by Oracle Corporation
JVM Runtime Data Areas
Memory Management and Garbage Collectors
Garbage Collection Tests
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
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
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