ACT now. Load Test.

Microsoft Application Center Test (ACT) is an updated version of Web Application Stress Tool (WAST), shipped with VS.NET. ACT provides the same basic capabilities as WAST, but is an updated code base user interface. While based on the .net Framework, it is capable of testing a remote site that is delivering content from ANY web based application.

Weighty pages can be tuned by taking care of bottlenecks identified after interpreting the ACT results and performance counters.