Low WiFi bandwidth in data reception (iperf)

Help and Support Vero 4K / Vero 4K +
1

Hi,

I have some issues with my Vero4k+ with Wifi.
The following command line delivers a result of 2.35 Mbits/secs

iperf3 -c 192xxx -i 1 -t 10 -R

Reverse mode, remote host 192.168.50.37 is sending
[ ID] Interval Transfer Bandwidth
[ 4] 0.00-10.00 sec 2.84 MBytes 2.38 Mbits/sec sender
[ 4] 0.00-10.00 sec 2.80 MBytes 2.35 Mbits/sec receiver

While the results seems a little more acceptable as a sender.

iperf3 -c 192xxx -i 1 -t 10

[ ID] Interval Transfer Bandwidth Retr
[ 4] 0.00-10.00 sec 144 MBytes 121 Mbits/sec 0 sender
[ 4] 0.00-10.00 sec 142 MBytes 119 Mbits/sec receiver

I use a dedicated Asus router RT-AX58U on a 5Ghz network.
I tried different position for the Vero4k+ with same results (no wall, etc.).

V4k+/OSMC is a great box and I would be pleased to find a way to solve this issue and to continue enhancing my personal media server. :slight_smile:

Any idea/support is welcome.

Vincent

2

Can you verify that 2.4Ghz and 5Ghz are on separate SSIDs?

3

Dear Sam,

Nice to meet you and talking with you.
Yes, SSIDs are dedicated to separated networks.

4

It would be good to see some logs, so we can see if there’s anything obvious there.

The difference in performance based on direction is quite surprising.

Some more questions:

  • What’s the distance from the device to AP?
  • Is the device you are running iperf on also connected via WiFi?
  • Can you try run iperf against another device?

Thanks

Sam

5

If you need specific log, please tell me, I will share them with you.

Regarding your points:

  • The device is 3/4 meters from the router.
  • The device running iperf as a server is connected to the same LAN, through WiFI, same SSID
  • The Vero4k+ delivers the same poor performances when communicating with another device (here located on an public iperf server):

iperf3 -c bouygues.iperf.fr -i 1 -t 10 -R

[ 4] 0.00-10.00 sec 4.57 MBytes 3.83 Mbits/sec 33 sender
[ 4] 0.00-10.00 sec 3.47 MBytes 2.91 Mbits/sec receiver

To compare the previous result, the same command line with any other device (from the lan to the public iperf server) delivers the following results:
[ 7] 0.00-10.03 sec 635 MBytes 531 Mbits/sec 0 sender
[ 7] 0.00-10.00 sec 626 MBytes 526 Mbits/sec receiver

Thank you
Vincent

6

Do you have a local iperf server on wired Ethernet?

I don’t recommend using an external service to check network connectivity. Almost certainly, your upstream bandwidth will be lower than your downstream Internet bandwidth.

Ideally it would be good to see dmesg.

8

I have installed a wired Eth iperf server.
Here are the results:
[ ID] Interval Transfer Bandwidth
[ 4] 0.00-10.00 sec 4.01 MBytes 3.36 Mbits/sec sender
[ 4] 0.00-10.00 sec 4.01 MBytes 3.36 Mbits/sec receiver

And, regarding the dmesg logs: here is the link

Thanks for your support

9

Your logs show this message every five seconds:

[  631.081992] Error getting the SSID

This is quite strange and I haven’t seen it before.
There is a newer WLAN driver in our 4.9 builds; but hopefully we can solve it on the stable 3.14 system.

  • What is the SSID of your WiFi AP?
  • Do you have VLAN enabled?
  • Are you able to try with another 5Ghz AP?

My guess is that the low performance is coming from blocking in the WiFi driver as a result of constantly trying to resolve the SSID.

10
  • My SSID is correctly matched at [ 7.309746] Connectting with a8:5e:45:10:41:24 channel (100) ssid “P80_5G”, len (6)
  • I do not use VLAN.
  • No.

Regarding your guess:
I have also seen this message when I was asked to check dmesg.
Apparently, there is no consequence on Wifi connection.
It comes from an application/service having, for some reason, a bad SSID to solve. :confused:

11

Dear Sam,

The SSID error came from wcid installation I did to investigate bandwidth issues.
I have removed it and rebooted the system.

I still have the same bandwidth issue (tested on a local eth iperf server).
I have updated the dmesg : here

Sorry for this inconvenience.
Vincent

12

*** Test by using another router
As suggested, I managed to get another router for the purpose of this test: TP-Link AC1750

I have re-installed the same testing conditions:

  • iperf server on eth
  • 5Ghz dedicated SSID

At the end, here are the results:
[ 4] 0.00-10.00 sec 15.0 MBytes 12.6 Mbits/sec sender
[ 4] 0.00-10.00 sec 15.0 MBytes 12.6 Mbits/sec receiver

I have investigated memory, process, disk and network test activity on Vero 4k+.
And there is nothing of interest which could explain such behaviour.

Any suggestion on further investigation?

13

Maybe changing the channel helps. Otherwise I think it must be environmental.

You say you checked process, did you also check kernel threads for high CPU use?

14

I changed the channel bandwidth from “Auto” to “160 Mhz” and, now it works !
[ 4] 0.00-10.00 sec 202 MBytes 169 Mbits/sec sender
[ 4] 0.00-10.00 sec 201 MBytes 169 Mbits/sec receiver

I also checked the environment and forced the channel to 40.
Regarding the transfer rate, all iperf tests have been played with -i 1 -t 10

Now it seems that everything works fine, including 4k video through WiFi.

The origin of the problem was not a big issue but, to be honest, as the Vero was the only device with such bad transfer rates, I was pretty convinced it was the source of the issue.

I hope this case will help someone else.

I was very surprised to read your quick answer, your involvement and your followup.
Thank you so much for your support.

1 Like
15

I’m really glad to hear that this is solved.

As you can probably imagine, WiFi issues can be quite complex to diagnose and I am sure that after making this adjustment other devices on your network will still benefit; although it may not be as obvious if they are not streaming video

Sam