It is a scenario too familiar to the software industry: new software is delivered to customers and suddenly unforeseen and devastating bugs cause everything to crash. Patterns for Performance and Operability is filled with practical, hands-on software development and testing techniques to ensure customers enjoy properly running software rather than complain about bugs and system crashes. The book explores in-depth nonfunctional design and testing that too many software professionals overlook to their peril. It shows how to avoid a range of real world user problems, unexpected data permutations, and unforeseen input that lead to software failure. Designers, developers and testers can refer to the book's catalog of defensive software patterns to guarantee high-quality performance.