rollingRestarts.js

var reloadAWorker = function(next){
  var count = 0;
  for (var i in cluster.workers){ count++; }
  if(workersExpected > count){
    startAWorker();
  }
  if(workerRestartArray.length > 0){
    var worker = workerRestartArray.pop();
    worker.send("stop");
  }
}

cluster.on('exit', function(worker, code, signal) {
  log("worker " + worker.process.pid + " (#"+worker.id+") has exited");
  setTimeout(reloadAWorker, 1000) // to prevent CPU-splsions if crashing too fast
});