If your reading a RedBook on WebSphere Performance Tuning and you haven't yet figured out what your Peak Average Load is, your performance testing is doomed to fail. This book guides you on the right path to the methodology that will work for your testing. It provides test plan guidelines and even sample scripts. In addition, there are several guidelines for analysis and interpretation.

The book only requires a couple of things to be a truely complete performance testing guide in my opinion: More detailed information and guidelines for Performance Testing Failover situations and slightly more concise guide for scripting. For the type of sites that you'll use this book for, you'll most likely have more complicated scripts and script requirements.

Over all, this book provides a great introduction of the core concepts and outlines quite a few of the more overlooked requirements in this increasingly important field.

I like the way this book starts out, showing the contrast between a bricks & mortar store and its online equivalent. This introduces the basics - throughput, transaction, page and user rates, response times and states. More than an easy to follow introduction, it contains all of the key elements of performance analysis, doled out in easy to understand chunks, and sets the stage for the rest of the book.

Every facet of a typical environment is covered, including Java server performance factors, external and internal factors related to networking, load balancers, protocol behavior, and Java internals. The chapter on performance profiles of common web sites is especially useful. Different site types are characterized in a set format that shows caching potential (of the site type), any special considerations, and specific performance testing considerations. This allows you to go directly to the type of site you are going to test, get the relevant information, then proceed to conduct the testing, which is covered in subsequent chapters.

The chapters on testing begin by showing how to develop the test plan, associated test scripts, and select the right tools to support the testing. The areas covered in these chapters are comprehensive. Actual test execution and results analysis are covered in equal detail, using examples and scenarios. One especially useful chapter is 13, Common Bottleneck Symptoms, which is useful to track the cause of observed results that do not match expected ones during testing.

This book goes beyond testing, though - it also covers capacity and performance planning, which is normally a discipline onto itself. Again, excellent advice and coverage of key points. The appendices are an invaluable collection of templates, worksheets and checklists.

I cannot recommend this book highly enough. It exemplifies top notch writing, is well illustrated, and is technically accurate, and based on proven approaches.

Ideas are well received by our team and book provide food for thought on diverse topics. We have continuous integration testing and continuous inspection (and adaptation) for performance testing and this book was very helpful.

The book is well-organized and thought out, and presents its information in an understandable, easy to follow fashion. I particularly like the inclusion of the test and capacity planning forms in the appendix. This gives readers the chance to put the information to work, instead of just giving case studies or presenting only theory.

A highly recommended and informational book.