Rob Pike's 5 Rules of Programming - Rule 1. You can't tell where a program is going to spend its time. Bottlenecks occur in surprising places, so don't try to second guess and put in a speed hack until you've proven that's where the bottleneck is. - Rule 2. Measure. Don't tune for speed until you've measured, and even then don't unless one part of the code overwhelms the rest. - Rule 3. Fancy algo...