我试图弄清楚为什么我的笔记本电脑上的本地主机网络性能如此缓慢。
我有一台英特尔 i5 6300u 2.4GHz，配备 8GB RAM（Windows 7 64 位）。
如果我跑
iperf -s
进而
iperf -c 127.0.0.1
这是我得到的输出：
D:\>iperf -c localhost -t 100 -i 5
------------------------------------------------------------
Client connecting to localhost, TCP port 5001
TCP window size: 208 KByte (default)
------------------------------------------------------------
[ 3] local 127.0.0.1 port 49743 connected with 127.0.0.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0- 5.0 sec 65.9 MBytes 111 Mbits/sec
[ 3] 5.0-10.0 sec 67.4 MBytes 113 Mbits/sec
[ 3] 10.0-15.0 sec 67.0 MBytes 112 Mbits/sec
[ 3] 15.0-20.0 sec 68.4 MBytes 115 Mbits/sec
[ 3] 20.0-25.0 sec 68.4 MBytes 115 Mbits/sec
[ 3] 25.0-30.0 sec 68.9 MBytes 116 Mbits/sec
[ 3] 30.0-35.0 sec 68.1 MBytes 114 Mbits/sec
[ 3] 35.0-40.0 sec 68.5 MBytes 115 Mbits/sec
[ 3] 40.0-45.0 sec 68.6 MBytes 115 Mbits/sec
[ 3] 45.0-50.0 sec 68.0 MBytes 114 Mbits/sec
[ 3] 50.0-55.0 sec 68.6 MBytes 115 Mbits/sec
[ 3] 55.0-60.0 sec 68.5 MBytes 115 Mbits/sec
这意味着我达到了最大值 115 Mbits（对于我来说，使用 localhost 有点太低了）。如果我-P 8使用多线程选项运行它，我达到最大值 189 Mbits/sec（稍好一点，但不是那么多）
CPU甚至达不到50％。
附加信息：
我使用远程节点（AWS 中的实例）进行了测试，速度较慢。我还使用 fast.com 进行了测试，速度可以达到 300Mbits/秒
使用多个流进行测试，最高速度为 187Mbits/秒
D:\>iperf -c 127.0.0.1 -P 20
------------------------------------------------------------
Client connecting to 127.0.0.1, TCP port 5001
TCP window size: 208 KByte (default)
Test with multiple streams (-P 20):
[ 3] local 127.0.0.1 port 65106 connected with 127.0.0.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 18] 0.0-10.2 sec 12.5 MBytes 10.3 Mbits/sec
[ 16] 0.0-10.2 sec 11.4 MBytes 9.36 Mbits/sec
[ 20] 0.0-10.3 sec 13.2 MBytes 10.7 Mbits/sec
[ 15] 0.0-10.3 sec 12.5 MBytes 10.2 Mbits/sec
[ 11] 0.0-10.3 sec 12.0 MBytes 9.78 Mbits/sec
[ 8] 0.0-10.4 sec 12.1 MBytes 9.82 Mbits/sec
[ 7] 0.0-10.2 sec 11.2 MBytes 9.26 Mbits/sec
[ 4] 0.0-10.3 sec 11.6 MBytes 9.50 Mbits/sec
[ 10] 0.0-10.2 sec 10.9 MBytes 8.92 Mbits/sec
[ 9] 0.0-10.3 sec 11.2 MBytes 9.20 Mbits/sec
[ 21] 0.0-10.2 sec 11.1 MBytes 9.13 Mbits/sec
[ 6] 0.0-10.3 sec 11.1 MBytes 9.04 Mbits/sec
[ 3] 0.0-10.4 sec 11.0 MBytes 8.91 Mbits/sec
[ 19] 0.0-10.4 sec 13.1 MBytes 10.6 Mbits/sec
[ 12] 0.0-10.4 sec 12.2 MBytes 9.89 Mbits/sec
[ 13] 0.0-10.4 sec 11.5 MBytes 9.27 Mbits/sec
[ 5] 0.0-10.4 sec 11.1 MBytes 8.95 Mbits/sec
[ 22] 0.0-10.5 sec 11.2 MBytes 9.02 Mbits/sec
[ 17] 0.0-10.5 sec 11.4 MBytes 9.08 Mbits/sec
[ 14] 0.0-10.5 sec 11.1 MBytes 8.89 Mbits/sec
[SUM] 0.0-10.5 sec 234 MBytes 187 Mbits/sec
关于环回上的 MTU：
D:\>netsh interface ipv6 show subinterfaces
MTU Stato Media Sense Byte in ingresso Byte in uscita Interfaccia
------ ----------------- ---------------- --------------- -----------
4294967295 1 0 6232 Loopback Pseudo-Interface 1
1500 2 2430 52320 Connessione rete wireless
1280 5 0 0 isatap.{ADB31CE7-8DB4-4DCC-903D-A3C2562C77CC}
1500 5 0 7856 Connessione rete wireless 2
1280 5 0 0 isatap.{611E9776-B58C-419F-8389-53BE2684DEEF}
1500 1 337173 301916 Connessione alla rete locale (LAN)
1280 5 0 0 isatap.enelint.global
1500 5 0 7856 Connessione rete wireless 3
1280 5 0 0 isatap.{6F6BA9BA-0A83-49A7-B76C-28AD125C7D36}
1500 5 0 6672 Connessione di rete Bluetooth
1280 5 0 0 isatap.{65692E26-21CE-42F7-A3D7-2C76564895A7}
1350 5 0 152 Connessione alla rete locale (LAN) 2
1280 5 0 0 isatap.{F61455EB-6826-432D-9F25-3BE44BC5E7CA}