Re: Sweating the small stuff: a lesson in optimisation

[RMGir]

Very entertaining read. I hope everyone reads all the way to the end - the last benchmark cracked me up.

The only question you didn't mention was "how fast is fast enough for this application?"

<Reveal this spoiler or all in this thread>

[Porculus]

That was part of the lesson, really. In practice any of the implementations would be "fast enough". The speed of this function does make a measurable difference to the run-time, but measurable isn't the same as significant; the entire program currently spends maybe two minutes a day running, so even if that was all spent in these routines, it still wouldn't make much difference.

(I didn't profile before I started; I went straight to optimisation mode because this particular routine involved Other People's Code and it Looked Inefficient. Hubris again.)

I wrote the final version purely out of curiosity, and it put things so firmly in perspective that I just had to write it up.