Slow UDP networking speed on Tinkerboard 2

[Hugo 0]

Hi,

Today while doing some network testing with the iperf command I realised the Tinkerboard 2 only seems to get up to 15Mbps when testing UDP.

Not sure what the cause is here, we're running the Debian image, haven't made any major changes, a different computer plugged into the same port gets 500Mbps, any ideas what it might be?

linaro@linaro-alip:~$ sudo iperf3 -c <Remote IP> -u -b 500M -t 20
Connecting to host <Remote IP>, port 5201
[  4] local <Local IP> port 58225 connected to <Remote IP> port 5201
[ ID] Interval           Transfer     Bandwidth       Total Datagrams
[  4]   0.00-1.00   sec  1.70 MBytes  14.2 Mbits/sec  217
[  4]   1.00-2.00   sec  1.74 MBytes  14.6 Mbits/sec  223
[  4]   2.00-3.00   sec  1.84 MBytes  15.4 Mbits/sec  235
[  4]   3.00-4.00   sec  1.75 MBytes  14.7 Mbits/sec  224
[  4]   4.00-5.00   sec  1.75 MBytes  14.7 Mbits/sec  224
[  4]   5.00-6.00   sec  1.74 MBytes  14.6 Mbits/sec  223
[  4]   6.00-7.00   sec  1.75 MBytes  14.7 Mbits/sec  224
[  4]   7.00-8.00   sec  1.84 MBytes  15.4 Mbits/sec  235
[  4]   8.00-9.00   sec  1.91 MBytes  16.1 Mbits/sec  245
[  4]   9.00-10.00  sec  2.08 MBytes  17.4 Mbits/sec  266
[  4]  10.00-11.00  sec  1.84 MBytes  15.4 Mbits/sec  235
[  4]  11.00-12.00  sec  1.91 MBytes  16.1 Mbits/sec  245
[  4]  12.00-13.00  sec  2.08 MBytes  17.4 Mbits/sec  266
[  4]  13.00-14.00  sec  2.23 MBytes  18.7 Mbits/sec  286
[  4]  14.00-15.00  sec  2.09 MBytes  17.6 Mbits/sec  268
[  4]  15.00-16.00  sec  2.25 MBytes  18.9 Mbits/sec  288
[  4]  16.00-17.00  sec  1.83 MBytes  15.3 Mbits/sec  234
[  4]  17.00-18.00  sec  2.00 MBytes  16.8 Mbits/sec  256
[  4]  18.00-19.00  sec  2.09 MBytes  17.5 Mbits/sec  267
[  4]  19.00-20.00  sec  1.99 MBytes  16.7 Mbits/sec  255
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth       Jitter    Lost/Total Datagrams
[  4]   0.00-20.00  sec  38.4 MBytes  16.1 Mbits/sec  0.072 ms  0/4916 (0%)
[  4] Sent 4916 datagrams

iperf Done.

 

Here's my random windows laptop on the same port:

.\iperf3.exe -c <Remote IP> -u -b 500M -t 20
Connecting to host <Remote IP>, port 5201
[  4] local <Local IP> port 51828 connected to <Remote IP> port 5201
[ ID] Interval           Transfer     Bandwidth       Total Datagrams
[  4]   0.00-1.01   sec  55.3 MBytes   460 Mbits/sec  7078
[  4]   1.01-2.01   sec  58.1 MBytes   489 Mbits/sec  7439
[  4]   2.01-3.00   sec  60.7 MBytes   512 Mbits/sec  7770
[  4]   3.00-4.03   sec  61.2 MBytes   500 Mbits/sec  7832
[  4]   4.03-5.03   sec  60.6 MBytes   508 Mbits/sec  7757
[  4]   5.03-6.00   sec  61.7 MBytes   532 Mbits/sec  7900
[  4]   6.00-7.00   sec  56.7 MBytes   475 Mbits/sec  7254
[  4]   7.00-8.00   sec  58.6 MBytes   492 Mbits/sec  7505
[  4]   8.00-9.00   sec  62.8 MBytes   527 Mbits/sec  8038
[  4]   9.00-10.01  sec  58.4 MBytes   485 Mbits/sec  7478
[  4]  10.01-11.00  sec  61.1 MBytes   518 Mbits/sec  7823
[  4]  11.00-12.00  sec  58.9 MBytes   494 Mbits/sec  7539
[  4]  12.00-13.00  sec  58.7 MBytes   493 Mbits/sec  7512
[  4]  13.00-14.00  sec  60.9 MBytes   511 Mbits/sec  7796
[  4]  14.00-15.01  sec  57.3 MBytes   474 Mbits/sec  7336
[  4]  15.01-16.00  sec  59.9 MBytes   509 Mbits/sec  7663
[  4]  16.00-17.00  sec  61.8 MBytes   517 Mbits/sec  7907
[  4]  17.00-18.00  sec  58.4 MBytes   491 Mbits/sec  7477
[  4]  18.00-19.01  sec  60.4 MBytes   502 Mbits/sec  7730
[  4]  19.01-20.01  sec  60.2 MBytes   507 Mbits/sec  7709
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bandwidth       Jitter    Lost/Total Datagrams
[  4]   0.00-20.01  sec  1.16 GBytes   500 Mbits/sec  0.060 ms  90/152542 (0.059%)
[  4] Sent 152542 datagrams

iperf Done.

 

The only thing I could think to check was the link speed on the interface and that Wi-Fi was disabled, both of which are set right.

linaro@linaro-alip:~$ ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: dummy0: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000
    link/ether 62:22:99:1b:5f:74 brd ff:ff:ff:ff:ff:ff
    inet6 fe80::80ab:a4a7:39b9:4e1e/64 scope link
       valid_lft forever preferred_lft forever
3: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 7c:10:c9:ee:05:7b brd ff:ff:ff:ff:ff:ff
    inet <Local IP>/24 brd <Local IP Broadcast> scope global noprefixroute eth0
       valid_lft forever preferred_lft forever
    inet6 fe80::7e10:c9ff:feee:57b/64 scope link
       valid_lft forever preferred_lft forever
4: wlp1s0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
    link/ether 48:e7:da:7b:3b:b7 brd ff:ff:ff:ff:ff:ff

Link speed:

linaro@linaro-alip:~$ dmesg | grep Gbps
[   14.133160] rk_gmac-dwmac fe300000.ethernet eth0: Link is Up - 1Gbps/Full - flow control off
[   18.176732] rk_gmac-dwmac fe300000.ethernet eth0: Link is Up - 1Gbps/Full - flow control off

TCP works fine, up to 800Mbps which is what we expect.

Any help appreciated thanks.

Edited February 22, 2023 by Hugo