Upload:
root@am335x-evm:~# iperf -c 192.168.1.20 -P 5 -t 60
------------------------------------------------------------
Client connecting to 192.168.1.20, TCP port 5001
TCP window size: 43.8 KByte (default)
------------------------------------------------------------
[  7] local 192.168.1.1 port 44694 connected with 192.168.1.20 port 5001
[  4] local 192.168.1.1 port 44688 connected with 192.168.1.20 port 5001
[  6] local 192.168.1.1 port 44692 connected with 192.168.1.20 port 5001
[  3] local 192.168.1.1 port 44686 connected with 192.168.1.20 port 5001
[  5] local 192.168.1.1 port 44690 connected with 192.168.1.20 port 5001
[ ID] Interval       Transfer     Bandwidth
[  4]  0.0-60.0 sec   253 MBytes  35.3 Mbits/sec
[  6]  0.0-60.0 sec   252 MBytes  35.2 Mbits/sec
[  7]  0.0-60.0 sec   252 MBytes  35.3 Mbits/sec
[  3]  0.0-60.0 sec   252 MBytes  35.3 Mbits/sec
[  5]  0.0-60.0 sec   252 MBytes  35.3 Mbits/sec
[SUM]  0.0-60.0 sec  1.23 GBytes   176 Mbits/sec

Download:
root@am335x-evm:~# iperf -s
------------------------------------------------------------
Server listening on TCP port 5001
TCP window size: 85.3 KByte (default)
------------------------------------------------------------
[  4] local 192.168.1.1 port 5001 connected with 192.168.1.20 port 35646
[  5] local 192.168.1.1 port 5001 connected with 192.168.1.20 port 35648
[  7] local 192.168.1.1 port 5001 connected with 192.168.1.20 port 35652
[  6] local 192.168.1.1 port 5001 connected with 192.168.1.20 port 35650
[  8] local 192.168.1.1 port 5001 connected with 192.168.1.20 port 35654
[ ID] Interval       Transfer     Bandwidth
[  7]  0.0-60.4 sec   437 MBytes  60.7 Mbits/sec
[  4]  0.0-60.4 sec   439 MBytes  61.0 Mbits/sec
[  8]  0.0-60.4 sec   432 MBytes  59.9 Mbits/sec
[  5]  0.0-60.4 sec   429 MBytes  59.5 Mbits/sec
[  6]  0.0-60.4 sec   434 MBytes  60.2 Mbits/sec
[SUM]  0.0-60.4 sec  2.12 GBytes   301 Mbits/sec