RUT200, CPU: 99%sirq

NETWORKING SOLUTIONS
1

The router’s internet traffic is very slow, with many disconnections.
I think the cause is about 99% of the CPU:SIRQ usage by a process named [mt76-tx phy0]

The ping 8.8.8.8 is over 400ms with more than 30% packet loss

BusyBox v1.34.1 (2024-08-08 07:42:09 UTC) built-in shell (ash)

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     Teltonika RUT2M series 2024
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   Device:     RUT200
   Kernel:     5.15.159
   Firmware:   RUT2M_R_00.07.08.2
   Build:      9f66e09309c
   Build date: 2024-08-08 08:13:39

# top

Mem: 66944K used, 57200K free, 600K shrd, 0K buff, 20392K cached
CPU:   0% usr   0% sys   0% nic   0% idle   0% io   0% irq  99% sirq
Load average: 14.10 13.63 13.20 14/73 6325
  PID  PPID USER     STAT   VSZ %VSZ %CPU COMMAND
  849     2 root     SW       0   0%  90% [mt76-tx phy0]

I want to upgrade the firmware remotely but it interrupts the download.

Moreover, last week, I replaced the RUT200 with a new one with the same configuration and firmware (that has worked well for months), but I’ve had the same problem.

Today I powered on and tested the old RUT200, in my office, and it works well !!

Maybe the issue is related to the mobile operator signal. I don’t know!!

Some one could help me, please ?
Roberto

3

Hello Roberto,

Thank you for reaching out.

The mt76-tx phy0 process is related to Wi-Fi transmission. It’s possible that a large number of wireless clients connected to the router are generating excessive traffic. Could you try temporarily disabling the wireless AP by navigating to Network → Wireless and checking if this improves performance?

Have you also tried performing a hard reboot of the router by unplugging and plugging the power cable back?

What is the signal reception level your router is currently receiving? You can check this in the Status → Network → Mobile page.

Additionally, performing a factory reset might be helpful as well.

Kind regards,

4

Hello Martynas,
your response is useful.

The hard reset allows me to access the web interface again and disable the WiFi radio.

Only 3 wireless clients were connected.

After stopping the mt76-tx phy0, the CPU load was reduced, but other processes took a high SIRQ CPU level.

Then, the ping from a PC connected via cable to RUT200 LAN IP goes better (0.6ms) but sometimes rises to 300ms for long periods with a lot of packet loss (30-40%)

I upgraded the firmware to 7.10.0 but nothing has changed.

5

Hi…
This three wireless clients… They are using Torrent?
" BitTorrent is a well-known P2P protocol that allows users to share files without a central server."

6

Yes,
but those clients are simple IoT devices that send electric consumption data from a production plant. So, they generate small and flat internet traffic…
Tomorrow I’ll go to the plant to investigate more
Thank you

7

Hi…

You can monitor alive your tcp/udp connections at your RUT.
Do a ssh to your device and type:

tail -f /proc/net/nf_conntrack

this command will list all live connections…

To stop… just press control + c . ok?

1 Like
8

Thank you to everybody,

In the end, using tail -f /proc/net/nf_conntrack I got a very poor Chinese device in a loop, generating 1.5GB/h outcoming traffic.

So the RUT200 was supporting a very high throughput. I switched off the poor device, everything is working well.

2 Likes
9

If you don’t mind, I would be interested to know what is this “very poor Chinese device”. In particular the ethernet and/or wifi chips.

10

It’s a PUSR model USR-DR404 v2.0.0

11

Did you have something connected to the RS485 line ?

12

Yes of course, but PUSR was configured as a Modbus passthrough server, listening from TCP and replying to an RTU slave.
It was pushing some data over the internet. I don’t know what.

13

I have no experience with this RS485 to IP converter, however I suspect that some serial parameters could be incorrect or there are retransmissions issues. But this is out of scope for this topic.