Oracle Parallel Processing

Preface

What is parallel processing? What does it have to do with Oracle? And how can you get the most out of Oracle’s parallel processing features? These are the questions this book attempts to answer. Oracle’s strong support for parallel processing sets it apart from other database systems on the market today. If you’re managing a large database, a database with a large number of concurrent users, or a database with high-availability requirements, you probably are already using at least some of Oracle’s parallel features. If not, you certainly need to investigate them.

Oracle’s support for parallel processing can be divided into two broad categories:

Oracle’s parallel execution features

Oracle’s support for multiple CPU systems allows you to leverage the power of two or more CPUs to complete a single task. The parallel execution features (provided as a standard part of the database) provide both speedup and scalability. When you use parallel execution features, individual tasks are completed faster than they would be otherwise, and you can increase throughput capacity simply by adding more CPUs and memory to your system.

Oracle Parallel Server (OPS)

While the parallel execution features allow you to leverage the power of many CPUs in a single system, Oracle Parallel Server (an extra-cost option) allows you to leverage the power of many systems against a single database. You can even combine the two features, taking advantage of the combined processing power of many CPUs in many systems, to handle large numbers of users or to complete large and complex jobs. Not only can you add more CPUs to individual systems in order to support growth, you also can add entire new systems. Oracle Parallel Server provides the highest scalability for data warehousing applications. Oracle Parallel Server also supports high availability. With multiple systems accessing a single database, if one system goes down, users can be switched to another, where they can continue to work.

The bottom line is that if you are an Oracle database administrator managing a database in which throughput, scalability, or high availability is important, you need to know the material in this book so you’ll be able to use Oracle’s parallel processing features to their best advantage.

Why We Wrote This Book

We specialize in managing Oracle Parallel Server databases, and we’ve experienced firsthand all the benefits that Oracle’s parallel processing features have to offer. We’ve also experienced a great deal of the pain that sometimes goes with these features. As we looked around the marketplace, we realized that there was no good, single source of information for DBAs who are just getting started with Oracle Parallel Server.

Oracle’s parallel server and parallel execution features are powerful and offer many benefits, but they carry with them a number of unique database administration challenges. The database creation process for OPS, for example, is somewhat different from that of a typical, non-OPS database. There are tuning issues that are unique to OPS, as well as some that are unique to environments using parallel execution features. We wrote this book to provide a single source of information that would help DBAs who are already experienced with Oracle make the transition to a parallel-processing environment.