code: function forkWorkers(numWorkers, env) {
  	var workers = [];
  	env = env || {};
  	for(var i = 0; i < numWorkers; i++) {
  		worker = cluster.fork(env);
  		console.info("Start worker: " + worker.process.pid + ' at ' + (new Date()).toISOString());
  		workers.push(worker);
  	}
  	return workers;
  }
docs: Fork workers.