Hi all,
With my VIM3 I recently run into an issue where the network performance was extremely poor. Investigation and googling led me to the similar problems described here:
Changing to 100MBit indeed improved the situation significantly. See the test results below. I tested with different cables (Cat6a which are proven working OK on a PC) and different devices (1Gbit switch port or 1Gbit router) on the opposite side of the cable.
The device was bought in Aliexpress “Khadas Official Store” ~ 1.5 year ago. Since then I used the device only occasionally for testing purposes. I had not noticed the problem probably because I was connecting it to 100MBit port before 
.
After so long time I am afraid I can hardly open a warranty claim, so I would like to kindly ask for you help, if there is something that can be done at home to fix the HW issue by a person with a limited soldering skills?
I first noticed the issue with Armbian, but to make sure I just tested the latest VIM3_Ubuntu-server-focal_Linux-5.16-rc2_arm64_SD-USB_V1.0.10-220108.img.xz and the results are the same
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# 1GBit test
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root@Khadas:~# iperf3 -R -c 192.168.1.41
Connecting to host 192.168.1.41, port 5201
Reverse mode, remote host 192.168.1.41 is sending
[ 5] local 192.168.1.43 port 36734 connected to 192.168.1.41 port 5201
[ ID] Interval Transfer Bitrate
[ 5] 0.00-1.00 sec 29.7 KBytes 243 Kbits/sec
[ 5] 1.00-2.00 sec 0.00 Bytes 0.00 bits/sec
[ 5] 2.00-3.00 sec 0.00 Bytes 0.00 bits/sec
[ 5] 3.00-4.00 sec 45.2 KBytes 371 Kbits/sec
[ 5] 4.00-5.00 sec 0.00 Bytes 0.00 bits/sec
[ 5] 5.00-6.00 sec 12.7 KBytes 104 Kbits/sec
[ 5] 6.00-7.00 sec 8.48 KBytes 69.5 Kbits/sec
[ 5] 7.00-8.00 sec 0.00 Bytes 0.00 bits/sec
[ 5] 8.00-9.00 sec 0.00 Bytes 0.00 bits/sec
[ 5] 9.00-10.00 sec 0.00 Bytes 0.00 bits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bitrate Retr
[ 5] 0.00-10.00 sec 126 KBytes 103 Kbits/sec 39 sender
[ 5] 0.00-10.00 sec 96.2 KBytes 78.8 Kbits/sec receiver
iperf Done.
root@Khadas:~# ethtool eth0
Settings for eth0:
Supported ports: [ TP MII ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Supported pause frame use: Symmetric Receive-only
Supports auto-negotiation: Yes
Supported FEC modes: Not reported
Advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Advertised pause frame use: Symmetric Receive-only
Advertised auto-negotiation: Yes
Advertised FEC modes: Not reported
Link partner advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Link partner advertised pause frame use: Symmetric
Link partner advertised auto-negotiation: Yes
Link partner advertised FEC modes: Not reported
Speed: 1000Mb/s
Duplex: Full
Port: Twisted Pair
PHYAD: 0
Transceiver: internal
Auto-negotiation: on
MDI-X: Unknown
Supports Wake-on: ug
Wake-on: d
Current message level: 0x0000003f (63)
drv probe link timer ifdown ifup
Link detected: yes
#####################################################################################
# 100MBit test
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root@Khadas:~# sudo ethtool -s eth0 speed 100 duplex full
root@Khadas:~# iperf3 -R -c 192.168.1.41
Connecting to host 192.168.1.41, port 5201
Reverse mode, remote host 192.168.1.41 is sending
[ 5] local 192.168.1.43 port 36738 connected to 192.168.1.41 port 5201
[ ID] Interval Transfer Bitrate
[ 5] 0.00-1.00 sec 11.2 MBytes 94.1 Mbits/sec
[ 5] 1.00-2.00 sec 11.2 MBytes 94.1 Mbits/sec
[ 5] 2.00-3.00 sec 11.2 MBytes 94.2 Mbits/sec
[ 5] 3.00-4.00 sec 11.2 MBytes 94.2 Mbits/sec
[ 5] 4.00-5.00 sec 11.2 MBytes 94.1 Mbits/sec
[ 5] 5.00-6.00 sec 11.2 MBytes 94.1 Mbits/sec
[ 5] 6.00-7.00 sec 11.2 MBytes 94.1 Mbits/sec
[ 5] 7.00-8.00 sec 11.2 MBytes 94.1 Mbits/sec
[ 5] 8.00-9.00 sec 11.2 MBytes 94.2 Mbits/sec
[ 5] 9.00-10.00 sec 11.2 MBytes 94.1 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bitrate Retr
[ 5] 0.00-10.00 sec 113 MBytes 94.4 Mbits/sec 0 sender
[ 5] 0.00-10.00 sec 112 MBytes 94.1 Mbits/sec receiver
iperf Done.
root@Khadas:~# ethtool eth0
Settings for eth0:
Supported ports: [ TP MII ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Supported pause frame use: Symmetric Receive-only
Supports auto-negotiation: Yes
Supported FEC modes: Not reported
Advertised link modes: 100baseT/Full
Advertised pause frame use: Symmetric Receive-only
Advertised auto-negotiation: Yes
Advertised FEC modes: Not reported
Link partner advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Link partner advertised pause frame use: Symmetric
Link partner advertised auto-negotiation: Yes
Link partner advertised FEC modes: Not reported
Speed: 100Mb/s
Duplex: Full
Port: Twisted Pair
PHYAD: 0
Transceiver: internal
Auto-negotiation: on
MDI-X: Unknown
Supports Wake-on: ug
Wake-on: d
Current message level: 0x0000003f (63)
drv probe link timer ifdown ifup
Link detected: yes
#####################################################################################
# Kernel version
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root@Khadas:~# uname -a
Linux Khadas 5.16.0-rc2 #1.0.10 SMP Sat Jan 8 13:31:00 CST 2022 aarch64 aarch64 aarch64 GNU/Linux
root@Khadas:~#
Thanks in advance,
Peter