Throughput of LAN7800 on Dual Gigabit Ethernet Carrier Board

Hi,
I’m testing the ethernet ports on Dual Gigabit Ethernet Carrier Board for CM4. I’m connecting a Raspberry Pi4 Model B and the carrier board together through an Ethernet Cat5e cable. Both board has the same setting of the latest OS version. I’m using iperf3 to test the throughput on the each port. The Raspberry Pi4 is set as a server and the CM4 on the carrier board is set as a client.

On eth1 ( port connected through LAN7800) the result is as follow

[ ID] Interval           Transfer     Bitrate         Retr  Cwnd
[  5]   0.00-1.00   sec  61.2 MBytes   513 Mbits/sec    0    296 KBytes
[  5]   1.00-2.00   sec  59.8 MBytes   502 Mbits/sec    0    313 KBytes
[  5]   2.00-3.00   sec  59.7 MBytes   501 Mbits/sec    0    328 KBytes
[  5]   3.00-4.00   sec  59.6 MBytes   500 Mbits/sec    0    328 KBytes
[  5]   4.00-5.00   sec  58.9 MBytes   494 Mbits/sec    0    345 KBytes
[  5]   5.00-6.00   sec  59.2 MBytes   496 Mbits/sec    0    345 KBytes
[  5]   6.00-7.00   sec  59.6 MBytes   500 Mbits/sec    0    345 KBytes
[  5]   7.00-8.00   sec  59.8 MBytes   501 Mbits/sec    0    345 KBytes
[  5]   8.00-9.00   sec  59.2 MBytes   497 Mbits/sec    0    345 KBytes
[  5]   9.00-10.00  sec  58.6 MBytes   491 Mbits/sec    0    345 KBytes
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bitrate         Retr
[  5]   0.00-10.00  sec   596 MBytes   500 Mbits/sec    0             sender
[  5]   0.00-10.00  sec   595 MBytes   499 Mbits/sec                  receiver

on eth0

[ ID] Interval           Transfer     Bitrate         Retr  Cwnd
[  5]   0.00-1.00   sec   109 MBytes   915 Mbits/sec    0    375 KBytes
[  5]   1.00-2.00   sec   111 MBytes   933 Mbits/sec    0    375 KBytes
[  5]   2.00-3.00   sec   111 MBytes   929 Mbits/sec    0    375 KBytes
[  5]   3.00-4.00   sec   110 MBytes   927 Mbits/sec    0    375 KBytes
[  5]   4.00-5.00   sec   110 MBytes   926 Mbits/sec    0    375 KBytes
[  5]   5.00-6.00   sec   103 MBytes   860 Mbits/sec    0    477 KBytes
[  5]   6.00-7.00   sec   112 MBytes   936 Mbits/sec    0    477 KBytes
[  5]   7.00-8.00   sec   111 MBytes   934 Mbits/sec    0    477 KBytes
[  5]   8.00-9.00   sec   110 MBytes   927 Mbits/sec    0    477 KBytes
[  5]   9.00-10.00  sec   111 MBytes   935 Mbits/sec    0    477 KBytes
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bitrate         Retr
[  5]   0.00-10.00  sec  1.07 GBytes   922 Mbits/sec    0             sender
[  5]   0.00-10.00  sec  1.07 GBytes   920 Mbits/sec                  receiver

As you can see above, the throughput on eth1 is almost half when compared to the eth0. Is it something I’m doing wrong on the testing or is it just the hardware limitation of the Carrier Board?

Hello, which carrier board are you using and can you please give me the SKU or link to the product details page?

Hi,

The SKU number for the product is 102110497. I’ve just found the solution though. I did not read the document till the end. There was a instruction on installing DT overlay for the chip. After following the instruction, I was able to get the throughput around the specified 1Gbits/s.

Thanks
Steven