protected function registerChildProcess(Process $process, string $poolName) : bool
    {
        array_push($this->processes[$poolName], $process);
        $workerPid = $process->getPid();
        $workerId = $this->config['server_id'] . '_' . $workerPid;
        $this->workerStates[$workerId] = Worker::WORKER_STATE_IDLE;
        $this->workerStats[$workerId] = 0;
        return true;
    }