string(249) "get document error：https://zhidao.baidu.com/search?lm=0&rn=10&pn=0&fr=search&dyTabStr=null&word=%E8%80%90%E5%8E%8B%E6%B5%8B%E8%AF%95%E6%96%B9%E6%B3%95%E5%8F%8A%E6%A0%87%E5%87%86 => Failed to connect to 125.88.227.171 port 38114: Connection refused"
耐压测试方法及标准
