string(258) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E5%B8%A6%E5%AE%BD%E7%9A%84%E8%AE%A1%E7%AE%97%E6%96%B9%E5%BC%8F%E6%98%AF%E4%BB%80%E4%B9%88 => Failed to connect to 101.89.117.144 port 38208: Connection refused"
带宽的计算方式是什么
