Optimizing Java

Chapter 4. Performance Testing Patterns and Antipatterns

Performance testing is undertaken for a variety of reasons. In this chapter we will introduce the different types of test that a team may wish to execute, and discuss best practices for each type.

In the second half of the chapter, we will outline some of the more common antipatterns that can plague a performance test or team, and explain refactored solutions to help prevent them from becoming a problem for teams.

Types of Performance Test

Performance tests are frequently conducted for the wrong reasons, or conducted badly. The reasons for this vary widely, but are often rooted in a failure to understand the nature of performance analysis and a belief that “something is better than nothing.” As we will see repeatedly, this belief is often a dangerous half-truth at best.

One of the more common mistakes is to speak generally of “performance testing” without engaging with the specifics. In fact, there are many different types of large-scale performance tests that can be conducted on a system.

Note

Good performance tests are quantitative. They ask questions that produce a numeric answer that can be handled as an experimental output and subjected to statistical analysis.

The types of performance tests we will discuss in this book usually have mostly independent (but somewhat overlapping) goals, so you should take care when thinking about the domain of any given single test. A good rule of thumb when planning a performance test ...