Optimizing Java using D

[Xinok via Digitalmars-d]

On Thursday, 3 July 2014 at 07:29:42 UTC, Wanderer wrote:
> Nobody, never, measures sort algorithms by amount of swaps.

Maybe not in swaps, but I have seen sorting algorithms measured 
similarly using reads and writes. As others have stated, it can 
be a useful metric if you're sorting a range of structs.

Another example, it's possible to implement an in-place merge 
sort. It performs just slightly more comparisons than a regular 
merge sort. However, it's still slower because it requires 
significantly more reads and writes.

It's not the only metric though, and other things are difficult 
to measure. A bottom-up heapsort performs fewer comparisons than 
quicksort, but quicksort is still faster. That's because 
quicksort runs over the range sequentially which makes it "cache 
friendly" whereas heapsort relies heavily on random access.

Metrics aside, nothing beats a good ol' benchmark.