Cluster.js

const cluster = require ('cluster');
const os = require ('os');

if (cluster.isMaster) {
  const cpus = os.cpus ().length;
  console.log (`Forking for ${cpus} CPUs`);
  for (let i = 0; i < cpus; i++) {
    cluster.fork ();
  }
  Object.values (cluster.workers).forEach (worker => {
    worker.send (`Hello Worker ${worker.id}`);
  });
} else {
  require ('./server');
}