That looks better. However, I am really not sure what you are trying to achieve here. You didn't specify any scheduler, it means your tasks will use a default scheduler and that scheduler uses threadpool [1] and it will never create 1M threads. And as there is no actual work performed in the Task, things will run reasonably fast.

I am having hard time understanding what you are trying to test here. I am worried that .NET code is not really testing what you think it is.

[1] https://msdn.microsoft.com/en-us/library/dd997402(v=vs.110)....