https://iperf.fr/
    https://iperf.fr/iperf-download.php#windows
    https://www.cnblogs.com/yaoyuanmengjing/p/7872242.html

    iperf-3.1.3-win32.zipiperf-3.1.3-win64.zip


    What is iPerf / iPerf3 ?
    iPerf3 is a tool for active measurements of the maximum achievable bandwidth on IP networks. It supports tuning of various parameters related to timing, buffers and protocols (TCP, UDP, SCTP with IPv4 and IPv6). For each test it reports the bandwidth, loss, and other parameters. This is a new implementation that shares no code with the original iPerf and also is not backwards compatible. iPerf was orginally developed by NLANR/DAST. iPerf3 is principally developed by ESnet / Lawrence Berkeley National Laboratory. It is released under a three-clause BSD license.
    iPerf features

    • TCP and SCTP
      • Measure bandwidth
      • Report MSS/MTU size and observed read sizes.
      • Support for TCP window size via socket buffers.
    • UDP
      • Client can create UDP streams of specified bandwidth.
      • Measure packet loss
      • Measure delay jitter
      • Multicast capable
    • Cross-platform: Windows, Linux, Android, MacOS X, FreeBSD, OpenBSD, NetBSD, VxWorks, Solaris,…
    • Client and server can have multiple simultaneous connections (-P option).
    • Server handles multiple connections, rather than quitting after a single test.
    • Can run for specified time (-t option), rather than a set amount of data to transfer (-n or -k option).
    • Print periodic, intermediate bandwidth, jitter, and loss reports at specified intervals (-i option).
    • Run the server as a daemon (-D option)
    • Use representative streams to test out how link layer compression affects your achievable bandwidth (-F option).
    • A server accepts a single client simultaneously (iPerf3) multiple clients simultaneously (iPerf2)
    • New: Ignore TCP slowstart (-O option).
    • New: Set target bandwidth for UDP and (new) TCP (-b option).
    • New: Set IPv6 flow label (-L option)
    • New: Set congestion control algorithm (-C option)
    • New: Use SCTP rather than TCP (—sctp option)
    • New: Output in JSON format (-J option).
    • New: Disk read test (server: iperf3 -s / client: iperf3 -c testhost -i1 -F filename)
    • New: Disk write tests (server: iperf3 -s -F filename / client: iperf3 -c testhost -i1)

    服务器端&客户端（保证服务端和客户端可以ping同）
    服务端执行：iperf3 -s
    客户端执行：iperf3 -c SERVER_IP
    测试UDP: 加 -u 参数
    在udp模式下，以100Mbps为数据发送速率，客户端到服务器192.168.1.1上传带宽测试，测试时间为60秒
    iperf3 -u -c 192.168.3.10 -b 100M -t 60
    客户端同时向服务器端发起30个连接线程，以5Mbps为数据发送速率
    iperf3 -u -c 192.168.81.37 -b 5M -P 30 -t 60
    以100M为数据发送速率，
    来自: http://man.linuxde.net/iperf