Working with Performance Hooks

import { performance } from "node:perf_hooks";
const t0 = performance.now();
work();
console.log("elapsed ms:", performance.now() - t0);

performance.mark("a");
work();
performance.mark("b");
performance.measure("work", "a", "b");

import { PerformanceObserver } from "node:perf_hooks";
const obs = new PerformanceObserver((items) => {
  for (const e of items.getEntries()) console.log(e.name, e.duration);
});
obs.observe({ entryTypes: ["measure", "function"] });

import { performance } from "node:perf_hooks";
const wrapped = performance.timerify(slowFn);
wrapped(input);