Performance anti patterns

Question

I am currently working for a client who are petrified of changing lousy un-testable and un-maintainable code because of \"performance reasons\". It is clear t

Answer 1

Julian Birch once told me:

"Yes but how many years of running the application does it actually take to make up for the time spent by developers doing it?"

He was referring to the cumulative amount of time saved during each transaction by an optimisation that would take a given amount of time to implement.

Wise words from the old sage... I often think of this advice when considering doing a funky optimisation. You can extend the same notion a little further by considering how much developer time is being spent dealing with the code in its present state versus how much time is saved by the users. You could even weight the time by hourly rate of the developer versus the user if you wanted.

Of course, sometimes its impossible to measure, for example, if an e-commerce application takes 1 second longer to respond you will loose some small % money from users getting bored during that 1 second. To make up that one second you need to implement and maintain optimised code. The optimisation impacts gross profit positively, and net profit negatively, so its much harder to balance. You could try - with good stats.