Parallel Environment for AIX 5L V4.1
Hitchhiker's Guide

Hitching a lift on the Vogon constructor ship

The Hitchhiker's Guide to the Galaxy begins with Arthur Dent, earthman and main character, being suddenly swept aboard an alien spaceship from his garden. Once on the ship, his new surroundings bewilder Arthur totally. Fortunately, Ford Prefect, Arthur's earth companion (who, as Arthur recently discovered, is actually an alien from a planet somewhere in the vicinity of Betelguese), is there to explain what is going on.

Just as Arthur had to get used to his new environment when he first left earth, this chapter will help you get used to the new environment you are in; the IBM Parallel Environment for AIX (PE). It covers:

• The IBM Parallel Environment for AIX
• The Parallel Operating Environment
• Starting the POE
• Running simple commands
• Experimenting with parameters and environment variables
• Using a host list file versus a job management system (LoadLeveler) for requesting processor nodes
• Compiling and running a simple parallel application
• Some simple environment setup and debugging tips.

This book contains many examples and illustrates various commands and programs as well as the output you get as a result of running them. When looking at these examples, keep in mind that the output you see on your system may not exactly match what is printed in the book. This is due to the differences between your system and ours. We have included the examples here just to give you a basic idea of what happens.

The IBM RS/6000^(R) World Wide Web site (as described in Bibliography), provides the sample programs, as they appear in this book, in source format. If you intend to write or use any of the sample programs, you should obtain the examples from the web site rather than copying them from the book. Because of formatting and other restrictions in publishing code examples, some of what you see here may not be syntactically correct. On the other hand, the source code on the web site has been tested and should work properly.

If you are unfamiliar with the terms in this chapter, the Glossary may be of some help.