This article provides information about the new Application Center Test (ACT) tool. You can use ACT to simulate load for your Web applications. By simulating load for your application, you can test concurrency issues, as well as better understand how your application behaves under stress.

The Web Application Stress tool previously provided this functionality. For more information about the Web Application Stress tool, see the "References" section.

Please note that testing load and concurrency by refreshing a browser is not considered a valid test.

When you use Application Center Test to stress test your Web server, you can see how your Web server reacts when several hundred users access your application at peak times. You can also use ACT to test the server-side components for performance, locks, and other scalability issues. In addition, you can test a Web application that relies on databases based on parameters such as concurrency, transactions, number of users, locks, pooling, and so on.

Application Center Test comes in one version, the Developer Edition, that is included with Visual Studio .NET Enterprise Developer and is recommended for optimizing code during the development process. You can use the Developer Edition directly within the Visual Studio .NET Integrated Development Environment (IDE), though with limited project configuration options. Advanced project configuration options are available when you open the project within the stand-alone ACT program.

For more information on how to create and configure ACT projects, refer to the product documentation and help files that are included with Application Center 2000 and Visual Studio .NET or the following MSDN Web site:

For additional information about the Web Application Stress tool, click the article number below to view the article in the Microsoft Knowledge Base: For more information, refer to the Microsoft Application Center Web site: