I am trying to profile virtual functions vs delegates

http://dpaste.dzfl.pl/dd10c841

  Num          Tree        Func        Per
  Calls        Time        Time        Call

      3     1019328      456148      152049     int main._testfooA(main.A)
      3     1809331      398939      132979     int main.testfooA(main.A)
      3      446842      382742      127580     int main.testfooB(main.B)


_testfooA is called when the delegate is null(this results in comparison that fails)

testfooA is called when the delegate is not null(which results in a comparison that passes and the delegate is called).

testfooB is simple virtual function calls.


What is Tree Time and how does it relate to performance? (call time is obvious)

Tree time is drastically different but the time per call is not (152 - 128)/128 ~= 20% slower.

I was interested in using the interface final pattern to provide default behavior but it seems slower than virtual calls. I was hoping that the null delegate test would be faster but I guess the branching thrashes the cache?


      1         176         176         176     int main.testfoo()

If I avoid virtual functions all together then the speed differences is immense, but it is over 800x slower. Not sure if the compiler is somehow optimizing out testfoo or if virtual function calls are really that slow. I do realize that the virtual functions and delegates are not doing much but it's still quite significant.