Performance Profiling

Overview

Optimizing without measuring is guessing. Guessing wastes time and often makes things worse.

Core principle: ALWAYS measure before optimizing. Intuition about performance is wrong more often than right.

Violating the letter of this process is violating the spirit of performance engineering.

The Iron Law

MEASURE FIRST, OPTIMIZE SECOND - NO PREMATURE OPTIMIZATION WITHOUT PROFILING DATA

If you haven't profiled it, you cannot optimize it. Hunches are not data.

When to Use