背景
调试需要知道两端是否达到千兆网速，跑个测试最直观。
方法
需要两台设备，都安装iperf工具。
服务端
$ iperf -s
------------------------------------------------------------
Server listening on TCP port 5001
TCP window size: 128 KByte (default)
------------------------------------------------------------
客户端
$ iperf -c 10.0.1.33
------------------------------------------------------------
Client connecting to 10.0.1.33, TCP port 5001
TCP window size: 65.0 KByte (WARNING: requested 64.0 KByte)
------------------------------------------------------------
[ 1] local 10.0.1.9 port 58847 connected with 10.0.1.33 port 5001
[ ID] Interval Transfer Bandwidth
[ 1] 0.00-10.02 sec 96.4 MBytes 80.7 Mbits/sec