def start_idle_workers
      workers.each do |worker|
        if worker.idle?
          worker.try_start
          if pid = worker.pid
            report_to_master("+#{pid},#{worker.queue_key}")
          end
        end
      end
    end
def start_idle_workers
      workers.each do |worker|
        if worker.idle?
          worker.try_start
          if pid = worker.pid
            report_to_master("+#{pid},#{worker.queue_key}")
          end
        end
      end
    end
Private.