I was profiling one of my favorite large PHP applications today using APD. I kept getting what seemed to be strange results -- it was telling me that bunch of defines statements (30+ of them) were responsible for an inordinately large percentage of the page generation time. On minimal pages it was as much as 37%. Even on the well-known largest of pages, they were still clocking in at a not insignificant 5%.
That just didn't seem possible.