Fastest way to sort an array in descending order

Question

Why is the following code

Array.Sort(values);
Array.Reverse(values);

much faster at sorting an array in descending order compared to

<

Answer 1

Because in your second version it has to invoke your (anonymous) function each time it does a compare and then call .CompareTo inside that, so you have two indirections, whereas otherwise it can use build-in comparisons (for primitive types).

Basically you pay for function call overhead which I bet are eliminated for native primitive types when doing these sorts of operations. Though technically possible (I think), I doubt the Jitter is able to completely inline them in your second case.