public function initPool($config) {
		if (!method_exists($this, 'getMinClient') || !method_exists($this, 'getMaxClient')) {
			throw new NotFoundException("Method getMinClient or getMaxClient not found");
		}
		$this->wait = new SplQueue;
		$this->connection = new SplQueue;
		$this->last_run_out_time = time();
		if (isset($config['min'])) {
			$this->min_client = intval($config['min']);
		}
		if (isset($config['max'])) {
			$this->max_client = intval($config['max']);
		}
		//建立最小连接
		$count = $this->getMinClient();
		while ($count--) {
			$this->createConnection();
		}
	}