Performance के Tips

const { performance } = require("perf_hooks");
const cache = new Map();
function slowSquare(n) { let x = 0; for (let i = 0; i < 1e6; i++) x = n * n; return x; }
function cached(n) { if (!cache.has(n)) cache.set(n, slowSquare(n)); return cache.get(n); }
cached(9);
const t0 = performance.now(); cached(9); const hit = performance.now() - t0;
const t1 = performance.now(); slowSquare(9); const miss = performance.now() - t1;
console.log("cache hit faster than recompute:", hit < miss);

// Output:
// cache hit faster than recompute: true

⚠️ Run this in your own terminal or Node.js environment.