Performance-oriented development in the commercial computing world (was: Fixed point financial data versus floating point)

There's an Apple person I share an IRC channel with. He says that developers have been using typical-consumer-spec machines rather than grossly overmuscled "developer" machines recently, specifically to dogfood their stuff properly. Yeah. Me too. I recently dipped a toe into evolutionary programming. This involved "running programs" many, many times over. The task was game playing, so this means running games with multiple individuals as players. My population consisted of 10000 individuals and I wanted to run ten times that many games before starting to evolve, in order to have some data to work with. This means not just a loop that iterates 100K times, but a loop that iterates 100K times with the body of the loop running, on the average, about two individuals' programs. I ran this on my fastest machine, of course (one core of a 1.2GHz Core 2 Duo). I was expecting it to take substantial time, as humans measure time - probably somewhere between a few seconds and a few minutes. It didn't. It finished so fast I had to check to verify it really did do what it was supposed to. But "take care of the pence and the pounds will take care of themselves". When I code, efficiency is always, at the very least, lurking at the back of my mind; I went thorugh my larval stage on a VAX-11/780 and some of the habits it produced will probably always be with me. I don't consider this a bad thing. Any hardware can be made to crawl by throwing a sufficiently large problem at it, and the more efficiently the code runs, the larger the problem required to do so. And, to tie it back into the list topic, it means I can, and usually do, write code that does useful stuff on classic machines. "Old" mindset FTW! /~\ The ASCII Mouse \ / Ribbon Campaign X Against HTML mouse at rodents-montreal.org / \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B