What is the reason behind this huge Performance difference in .Net 4

Question

I was just doing some research on RedBlack Tree. I knew that SortedSet class in .Net 4.0 uses RedBlack tree. So I took that part out as is using Reflector and created a RedBlack

Answer 1

If the difference wasn't that big I would suggest that the cause is that the .NET assemblies are NGen-ed and so they are already translated to native code. In the case of your class the time to compile the IL code into native code is amortized over the time of your test. How does increasing the number of loop iterations affect the times?