Scalability Factors of Jmeter In Performance Testing Projects

Testing web applications for performance is fundamentally different and complex than testing them for functional correctness. Various flavors of load generation tools are available for simulating the expected load levels on servers, network or web application to test their ability to sustain concurrent heavy load under realistic conditions. In order to
carry out effective performance testing of web applications one has to ensure that sufficiently powerful hardware is used to generate required load levels. At the same time, one would prefer to avoid investing in unnecessarily expensive hardware “just to be sure”. Having an effective model for estimating the load generation capabilities of load generation tools on different hardware configurations can greatly help in taking care of both these requirements.

Unfortunately, the only such model we currently have is the simplistic set of benchmarks offered by different Commercial Performance test tool vendors. These benchmarks spell out how many “virtual users” their tool can simulate on different hardware configurations. In fact the load generation capability of any tool is a function of multiple factors and not just the underlying hardware configuration. Hence, the simplistic model is therefore not usable in practice. Some of the other factors that affect the load generation capacity of a tool include application response sizes, application response times and the complexity of client-side activity.