Sun Performance and Tuning: Java™ and the Internet, Second Edition

Chapter 3. Performance Measurement

In some cases, it is obvious that there is a performance problem; when it is fixed, there may be a noticeable improvement and your job is finished. It is much more common for performance tuning to consist of many small cumulative steps. Some of the steps may reduce performance overall or make one part of the system faster at the expense of another part of the system.

Problems can arise when it is necessary to quantify the changes or to measure minor performance changes in complex systems. If the aim of the work is to improve the performance in a well-defined benchmark, such as one of the SPEC or TPC measures, then the measurement can be well defined. In real life, it may be necessary to design a controlled ...