As an open source solution to the load testing demands of complicated Web 2.0 applications, Tsung offers engineers a cost effective and thorough means of testing. Written in the concurrency language of Erlang, Tsung is dedicated to providing an intense load while running a software stress test. Capable as well of running in a distributed mode, Tsung can simulate thousands of users accessing resources at the same time. With a small group of machines, Tsung can provide a load consisting of over 10,000 distinct users.

This is an invaluable tool in determining the readiness of a web server for the stresses of real world application. It is difficult to provide an adequately realistic test without the assistance of software testing utilities. Tsung not only tests for performance under heavy loads, but also for the correctness of server response. The user may enter a regex pattern for the software to recognize. This pattern may be an error code, or a segment of the site that should appear if the software is working properly.

In addition to testing the correctness of server response, Tsung includes a full report on the performance of the server under load. This report includes response and connection times. Tsung is also capable of gathering server hardware statistics, such as CPU, memory, and network traffic. Better yet, these statistics are gathered in real time, making them immediately available. This can be highly useful when working with a large project that could take days to properly test.

As an open source application, Tsung is broadening its base of features every day. Some of the latest additions include a MySQL benchmarker, and an XML based session recorder for building dynamic transaction scenarios. With Tsung's XML based system, users do not have to program complicated lengths of code in order to construct a simple transaction between the client and server.

The Tsung model provides excellent flexibility and affordability to the engineering community. The program lacks some of the flourishes, or bells and whistles, of expensive enterprise editions. A live transaction recorder is one of the most obvious omissions. Although users are able to write dynamic scenarios in an easy to understand XML based format, they cannot build a scenario by simply interacting with the application, as other systems can. All the same, Tsung is an excellent choice when heavy duty load testing is needed, without the hefty price tag.

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Tsung-User-Manual.pdf	588.03 KB