无法关闭workerman进程

这是Laravel框架调用Workerman

<?php

namespace App\Console\Commands;

use Illuminate\Console\Command;
use Illuminate\Console\ConfirmableTrait;
use Workerman\Worker;
use PHPSocketIO\SocketIO;
use Config;

class Workerman extends Command
{
    use ConfirmableTrait;

    /**
     * The name and signature of the console command.
     *
     * @var string
     */
    protected $signature = 'workerman:server {action} {-d|daemon=default}';

    /**
     * The console command description.
     *
     * @var string
     */
    protected $description = 'Run Workerman Server.';

    /**
     * Create a new command instance.
     *
     * @return void
     */
    public function __construct()
    {
        parent::__construct();
    }

    /**
     * Execute the console command.
     *
     * @return mixed
     */
    public function handle()
    {
        global $argv, $argc;

        $action = $this->argument('action');

        if (is_null($this->option('daemon'))) {
            $argv = ;
            $argc = 3;
        } else {
            $argv = ;
            $argc = 2;
        }

        switch ($action) {
            case 'start':
                $port = Config::get('workerman.server.port');
                $events = Config::get('workerman.events');

                $server = new SocketIO($port);

                foreach ($events as $event) {
                    new $event($server);
                }

                Worker::runAll();

                break;
            case 'stop':
                Worker::stopAll();

                break;
            case 'status':
                $this->info(Worker::getStatus());

                break;
            default:
                $this->error($action . ' action does not exist, try one one thoses : start, stop, status');
                break;
        }
    }
}

我用 php artisan workerman:server start -d 可以正常启动，但是用 php artisan workerman:server stop 却无法停掉workerman进程。