Foundations of Software and System Performance Engineering: Process, Performance Modeling, Requirements, Testing, Scalability, and Practice

Chapter 11. Scalability and Performance

Scalability is a highly desirable and commercially necessary feature of many systems. Despite that, there is no universally accepted definition of it. There is no hard-and-fast rule about how to achieve it, although the factors that might undermine it are often readily identifiable and easily understood. In this chapter we shall explore some definitions of scalability. We shall identify practices and system characteristics that are conducive to it and patterns and characteristics that can undermine it. Scalability pitfalls will be explored. We shall show how to plan performance tests to verify scalability and interpret the test results accordingly.

11.1 What Is Scalability?

Scalability is a desirable attribute ...