Software Mistakes and Tradeoffs

5 Premature optimization vs. optimizing the hot path: Decisions that impact code performance

This chapter covers

• When premature optimization is evil
• Finding the hot path in your code using performance testing and measurements
• Optimizing the hot path

There is an old computer science saying that premature optimization is the root of all evil. This has a solid background because it’s accurate for a lot of use cases. Without any input data about expected traffic and a service level agreement (SLA), it’s hard to reason about your code and its required performance. Optimizing random paths in code in such a situation is like shooting in the dark. You will complicate your code without a sane reason.

Note SLA specifies the amount of traffic the service ...