The Grinder is a JavaTM load-testing framework. It is freely available under a BSD-style open-source license.
The Grinder makes it easy to orchestrate the activities of a test script in many processes across many machines, using a graphical console application. Test scripts make use of client code embodied in Java plug-ins. Most users of The Grinder do not write plug-ins themselves, instead they use one of the supplied plug-ins. The Grinder comes with a mature plug-in for testing HTTP services, as well as a tool which allows HTTP scripts to be automatically recorded.
The Grinder was originally developed for the book Professional Java 2 Enterprise Edition with BEA WebLogic Server by Paco Gómez and Peter Zadrozny. Philip Aston took ownership of the code and reworked it to create The Grinder 2. Philip continues to enhance and maintain The Grinder, and welcomes all contributions. Recently Peter, Philip and Ted Osborne have published the book J2EE Performance Testing which makes extensive use of The Grinder