Simple code execution measurement

measure-code-execution-in-js.js

const start = new Date();
const hrStart = process.hrtime();

// process.hrtime();
// https://nodejs.org/api/process.html#processhrtimetime
// [seconds, nanoseconds]

setTimeout(() => {
 
  const end = new Date() - start;
  const hrEnd = process.hrtime(hrStart);

  console.log(`Exec time: ${end}`);
  console.log(`Exec time hr: ${hrEnd[0]} sec and ${hrEnd[1] / 1000000} ms`);
  

}, Math.ceil(Math.random() * 3000));