When you start looking for ways to make your scripts run faster,
it's often natural to look for the worst code and start fixing
things from there. However, this isn't usually the way to get
the most improvement bang for your coding buck.
Instead of looking for the ugliest code, take a look at your
site and figure out what gets run the most. Your home page and
template files that get included over and over are the perfect
places to start. Start making your changes here where they can
really pay off. Getting a script that runs once a day to run
twice as fast is certainly nice, but shaving a couple extra CPU
cycles off code which runs on every page will yield far more
By the same rational, when attempting to streamline any given
set of code, pay particular attention to code inside of loops.
Similarly to above, fixing a line of code that runs once will
certainly help, but finding a speed-bump inside a loop can
pay off hundreds of times over with each call to the page.