swoole定时器莫名的自动关闭了，但是所有进程都正常运行？

<code>function onWorkerStart(swoole_server $serv, $worker_id)
    {
        
        $this->loger->write_log('info',"Work_id " . $worker_id . " start \n");
        //如果当前运行的进程是task进程
        if($worker_id < $serv->setting['worker_num']) 
        {
            //开始执行任务
            $serv->task($worker_id);
        }     
        //添加定时器 只在第一个worker启动时创建一个定时器 来定时检索有没有要推送的消息
        if($worker_id == 0)
        {
            //创建定时器
            $timer = $serv->tick(3000,function ($timer_id){
                $db = new DBO(config_item('mall_db_config'));
                //获取所有未发送的推送消息
                $query_param = array('limit'=>100,'order'=>'createon asc','where'=>'msg_status = 0');
                $msgs = $db->select('t_msg_push',
                            array('id','mall_id','member_id','vpl','in_time','out_time','park_code',
                                'pay_points','park_duration','residual_points','msg_type'),
                            $query_param
                        );
                if(!empty($msgs))
                {
                    push_msg($msgs,$db);
                }
                else
                {
                    simple_log('No message to send.');
                }
                //关闭数据库连接
                $db->close();
            });
        }
    }</code>

<code>function onWorkerStart(swoole_server $serv, $worker_id)
    {
        
        $this->loger->write_log('info',"Work_id " . $worker_id . " start \n");
        //如果当前运行的进程是task进程
        if($worker_id < $serv->setting['worker_num']) 
        {
            //开始执行任务
            $serv->task($worker_id);
        }     
        //添加定时器 只在第一个worker启动时创建一个定时器 来定时检索有没有要推送的消息
        if($worker_id == 0)
        {
            //创建定时器
            $timer = $serv->tick(3000,function ($timer_id){
                $db = new DBO(config_item('mall_db_config'));
                //获取所有未发送的推送消息
                $query_param = array('limit'=>100,'order'=>'createon asc','where'=>'msg_status = 0');
                $msgs = $db->select('t_msg_push',
                            array('id','mall_id','member_id','vpl','in_time','out_time','park_code',
                                'pay_points','park_duration','residual_points','msg_type'),
                            $query_param
                        );
                if(!empty($msgs))
                {
                    push_msg($msgs,$db);
                }
                else
                {
                    simple_log('No message to send.');
                }
                //关闭数据库连接
                $db->close();
            });
        }
    }</code>