OpenSTA provides many of the features of the high end (i.e. Load Runner) web application performance testing tools. The OpenSTA model is based on a threaded model approach under which each simulated user (Virtual User) performs operations against a website. Potentially thousands of Virtual Users can be executed in parallel thereby approximating the expected volumes web traffic to your application.

Httperf uses call backs on open sockets to monitor and respond to simulated traffic. The advantage of the httperf approach is that large volumes of traffic can be generated; the disadvantage (over a tool such as OpenSTA) is that the nature of the traffic is simple http calls, although other plug ins may add to the core feature set.

Using Mock Services in performance testing

The challenges of performing component performance testing can be addressed with mock objects and a test harness. This article describes an overview of load testing Web services using mocked up services.

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