protected function shutdownWorkers()
    {
        $workers = Resque_Worker::all();

        foreach ($workers as $worker) {
            list($name, $pid, $queues) = explode(':', (string) $worker);
            posix_kill((int) $pid, SIGQUIT);
        }

        $this->output->writeln('<info>SIGQUIT sent to '.count($workers).' workers.</info>');
    }