Is there any good free .net profiler available?
Prof-It is an easy-to-use standalone profiler for C# that measures execution frequencies for each statement while keeping the instrumentation of the source code to a minimum. Prof-It is distributed under the terms of the GNU General Public License.
eqatec The EQATEC Profiler is a code profiler, not a memory profiler. So it's all about making your app run faster, not about tracking objects and memory.
SlimTune is a lesser known but very good .NET profiler. It does not support memory profiling, but on the performance profiling side, its author claims it has reached feature parity with NProf. My experience with it is very positive: it "just works".
I do a lot of work in .net, and whenever there is a performance problem, like the app takes too long to load, or messing with 3rd-party controls seems to take uncomfortably long, by the time somebody figures out how to fire up a profiler, this method tells what the problem is.
It gets a lot of disbelief because it's not a separate tool, it's just a way of using the IDE, and the disbelief persists even after it nails the problems.