code: function lifecycleTimeoutHandler() {
    if (shutdownCalled) {
      return;
    }
  
    verbose('workers have reached the end of their life');
  
    master.restart(function () {
      if (!shutdownCalled) {
        lifecycleTimer = setTimeout(lifecycleTimeoutHandler.bind(master), config.timeouts.maxAge);
      }
    });
  }
docs: Called when workers have reached the end of their lifespan
  
  @private