If you are looking for a book that describes how to approach and carry out a performance testing project, don’t look further. Get a copy of The Art of Application Performance Testing: Help for Programmers and Quality Assurance (O’Reilly, 2009). In it Ian Molyneaux manages to cover, in 160 pages, a crucial topic that is not only often forgotten in real projects, but also by authors. In fact, on the one hand, I know few companies that take performance testing seriously. What a shame! On the other hand, I am aware of few books that cover that particular topic. In my opinion, these two facts are not unrelated at all.

Let me shortly describe the five chapters of the book. Chapter 1, even though it is entitled Why Performance Test?, it focuses on the most common reasons why projects fail because of bad performance. Chapter 2, The Fundamentals of Effective Application Performance Testing, describes the ten essential requirements to plan an effective performance testing strategy. Chapter 3, The Process of Performance Testing, introduces several checklists that describe which activities have to be carried out for every step of a performance testing project. To do so the author also introduces two case studies based on real projects. Chapter 4, Interpreting Results: Effective Root-Cause Analysis, shows how to use the information provided by a performance testing tool to do a root-cause analysis. Also in this chapter examples taken from real projects are used. Chapter 5, Application Technology and Its Impact on Performance Testing, gives some guidance on how to deal with technologies and products like AJAX, Citrix, HTTP, Java, SAP and SOA.
To have a detailed look at the content you can take advantage of Google Books.

As you can see, what it is not covered is a performance testing tool. In other words, only the methodology is fully described. This is, in my opinion, not a problem. Not only because it is clearly out of scope, but also because the documentation provided with the performance testing tool of your choice should provide that information.

All in all, a very good book. I wish I would have read it several years ago!