1

After restarting the laptop, the wi-fi remains at the level of 50-60 Mbps, but after a while it starts to fall to 10 Mbps, then it is in a constant interval from 3-30 Mbps (the reason for such instability is not clear). At the same time, for example, loading a page can take a long time, but watching a video on YouTube (without rewinding) in 1080 can be done without problems (while maintaining quality).

This problem is seen only under Linux. There were no problems in Windows.

 - lspci
07:00.0 Network controller: Qualcomm Atheros QCA9377 802.11ac Wireless Network Adapter (rev 31)

 - lspci -nnk | grep -A2 0280
07:00.0 Network controller [0280]: Qualcomm Atheros QCA9377 802.11ac Wireless Network Adapter [168c:0042] (rev 31)
    Subsystem: Lenovo QCA9377 802.11ac Wireless Network Adapter [17aa:0901]
    Kernel driver in use: ath10k_pci

After reboot speed.

watch iwconfig

Wifi speed after reboot

After some time. It may seem that the Internet speed is normal, but at the beginning of the test the speed was 2-3 Mbps, then it began to grow to 50 and at the end it was 60. This can be seen on the chart.

enter image description here

Next test. enter image description here enter image description here

RdEErAqUa
  • 33
  • Bit of a long shot but could it be a heat related issue? Upon a (cold) reboot the laptop may be cooler and then as time progresses, the laptop gets hotter and the Wi-Fi performance drops. I have this issue with an old MacBook Pro, in a very hot (no air-con) room. Additional fans help solve my issue, although not totally fix it. Is the machine dual boot? That is to say, does the Wi-Fi perform better under Windows or some other OS? Is this an Ubuntu (and Ubuntu drivers) specific issue? – Greenonline Feb 28 '21 at 15:39
  • There were no such problems under Windows. There was definitely no overheating (the sensors show the temperature in the range of 60-70 degrees). – RdEErAqUa Mar 01 '21 at 08:00

2 Answers2

1

After much research, I came to the only method that helped me -> Wifi slow, temporarily fixed by resetting the connection.

I will leave the answer here, as I will supplement it if I encounter same problems in future.

  1. Set channel width on the router to 20 mhz in the 2.4GHz.
  2. Choose a specific channel, not automatic on the router(i choise 11).
  3. Set your regulatory domain if it not done yet.
sudo iw reg get

If you see 00, then find your ISO 3166-1 alpha-2 in http://en.wikipedia.org/wiki/ISO_3166-1_alpha-2, for example i will use UA - Ukraine, and you use your country code.

Next use that command

sudo iw reg set UA

Next set it permanently

gksudo gedit /etc/default/crda

You will see something like REGDOMAIN=. Set it to your country code.

REGDOMAIN=UA

If you want to check the stability of your internet connection, then use the following command. and pay attention to the parameter

ping 8.8.8.8

This is how I tested the changes. Before these changes, the time difference was huge, after - no.

After all this, the wifi works almost perfectly. Since it worked perfectly on all other devices before these changes, I believe that the problem was in my software on ubuntu, so I will leave this question and answer here.

RdEErAqUa
  • 33
-2

It's a driver issue. It looks like easiest way to fix it is to replace the Wi-Fi module from Qualcomm with one from Realtek or some other vendor.

Greenonline
  • 2,081
Artem Tokarev
  • 1
  • 2
    Changing a Wi-Fi module on a laptop is no trivial matter. The module may not be available for that particular model. – Greenonline Feb 28 '21 at 15:33