The investigation process for performance work: defining measurable goals, recording a baseline, characterising before diagnosing, falsifiability, fixed-work speedup bounds, experimental design, and validating by mechanism rather than by coincidence. Use when starting a performance investigation, when a fix is credited to a deploy that also restarted the process, when an optimisation is proposed without a measurement, when a benchmark result changes with the duration of the run, when an investigation has run for days without refuting a hypothesis, or when "it's fine in staging" is the explanation. Does not cover which tool to run (jfr-and-async-profiler), the statistics o…
