Ants Performance Profiler is Red Gate's performance testing tool for the .NET Framework.
As a software developer, I've learned over the years that the 80/20 rule applies to so many aspects of programming. Usually in a software application 20% of the code will be in use 80% of the time. You might also find that 80% of your database calls are made using just 20% of your core stored procedures. This factor makes it crucial to get the performance tuning right on your code. Tweaking code performance of frequently used functions can dramatically speed up your applications. Since sometimes only minor changes are often required, a small amount of work can lead to much faster applications.
Ants Performance Profiler works with the two most common .NET programming languages - C# and VB.NET. A variety of .NET applications can be profiled, including Windows Services as well as standard desktop Windows applications. It's also able to performance test ASP.NET, Sharepoint and Silverlight web application code. Ants Profiler can be controlled from within the Visual Studio developer environment.
The nice thing about Ants Performance Profiler is that it can attach to a running process, so if you want to profile an application you don't even need to restart it.