Why? Is that the place where your program is spending too much time?

If you really need to find out, I suggest you familiarise yourself with the Benchmark module. But make sure you don’t miss Zed Shaw’s article Programmers Need To Learn Statistics Or I Will Kill Them All.

You’ll also want to know what Perl actually makes of your code; B::Deparse will help you with that.

Makeshifts last the longest.