HP-UX Programmer's Guide for Java 2
Table Of Contents
- Table of Contents
- 1 Introduction
- 2 HotSpot Technology Tools and Commands
- 3 Configuration for Java™ Support
- 4 Performance and Tuning
- 5 Measuring System Performance
- 6 Using Threads
- 7 Using Signals
- 8 Using Java™ 2 JNI on HP-UX
- 9 Expanding Memory
- Determine your requirements
- Memory layout under HP-UX 11.0 (PA-RISC only)
- Additional memory available under HP-UX 11i (PA-RISC only)
- Allocating physical memory and swap in the Java™ heap
- Useful key command-line options for allocating memory
- Application-dependent considerations using large heap size HP-UX 11i PA-RISC
- Expanding heap size in native applications on PA-RISC HP-UX 11.11 and later releases
- Expanding heap size in native applications on Integrity HP-UX 11.23 and later releases
- Expanding heap size in HP-UX PA-RISC
- Expanding heap size in HP-UX Integrity
- 10 Diagnosing Memory Leaks
- A JDK/JRE 6.0.n and 7.0.n Usage Notes
- Using Java 2 JNI on HP-UX
- Garbage collection
- Asian TrueType fonts and Asian locales
- Date/Time methods defaults
- Profiling
- Compatibility with previous releases
- Java Cryptography Extension (JCE) policy files
- Configuring the Java Runtime Plug-In
- CLASSPATH environment variable
- Java Web Start technology usage
- Upgrading from a previous Java Web Start version
- IPv6 support
- Allocation Site Statistics and Zero Preparation -Xverbosegc
- JDK 6.0.04 flags
- GC log-rotation support
- NUMA collector enhancements
- ThreadDumpPath support
- Garbage-First garbage collector (-XX:+UseG1GC)
- jmap, jinfo, and jstack tools included in JDK 6.0.03
- Additional Java Web Start documentation
- B JDK/JRE 5.0.n Usage Notes
- Using Java 2 JNI on HP-UX
- Garbage collectors: Parallel and Concurrent Mark Sweep
- Allocating physical memory and swap in the Java heap
- Asian TrueType fonts and Asian locales
- Date/Time methods defaults
- Profiling
- Closing a socket (PA-RISC only)
- Compatibility with previous releases
- Java Cryptography Extension (JCE) policy files
- Allocation Site Statistics and Zero Preparation -Xverbosegc
- IPv6 support on Java 5.0
- GC log-rotation support in 5.0
- ThreadDumpPath support in 5.0
- Dynamically loaded libraries in 5.0
- Performance improvement for String.intern()
- Configuring the Java Runtime Plug-In
- CLASSPATH environment variable
- Java Web Start technology usage
- C SDK/RTE 1.4.2.n Usage Notes
- Removing support for unwanted architectures in the JRE
- Support for dynamic thread local storage (TLS)
- Signal Chaining functionality
- Using Java 2 JNI on HP-UX
- HotSpot JVM options
- Garbage collectors: Parallel and Concurrent mark sweep
- Allocating physical memory and swap in the Java heap
- Asian TrueType fonts and Asian locales
- Date/Time methods defaults
- Profiling
- Closing a socket when accept or read is pending (PA-RISC) - new patch information!
- Compatibility with previous releases
- Runtime Plug-In usage and configuration
- GC log-rotation support
- ThreadDumpPath support
- D Additional Resources
- Index

4 Performance and Tuning
Unless specified otherwise, the information in this chapter applies to both HP-UX
PA-RISC and HP-UX Itanium® Processor Family systems.
In your application design, remember that performance is designed into your
application. Don't let it be an area ignored until just prior to release.
In general, we've found these three recommendations useful for program design.
1. Maximize thread lifetimes and minimize thread creation/destruction cycles. Your
application can spend more time doing application specific work.
2. Minimize contention for shared resources to eliminate long queues waiting for
mutexes. Your application will be scalable, because it won't be serialized on one
lock.
3. Minimize creation of short-lived objects. Your application can spend more time
working rather than garbage collecting.
Our Java™ Information Library can be located at: http://www.hp.com/go/hpux-java-docs
and also provides a collection of tutorials and articles on performance tuning and other
subjects.
In addition, you may want to download HP's set of performance tools:
• HPjmeter performance analysis tool
• HPjconfig configuration tool for tuning HP-UX
34 Performance and Tuning