Interruptions in wifi connectivity every 5 minutes (300 seconds)

[kenakofer]

• [X] I've run a search on the existing bug reports to make sure I'm not filing a duplicate (you can use the search box at the top left corner)
• [X] I've read the Regolith documentation and didn't find any relevant topic
• [X] I tried asking on Slack (especially for configuration related issues). Thread here

Describe the bug My poorly-supported-on-linux rtl8821ce wifi card has interruptions in connectivity (as judged by a long ping to the router) every 5 minutes and 3 seconds (between 303 and 304 seconds). The connection cuts out for about 3 seconds. This only occurs while I am logged into Regolith, not when logged into Ubuntu or gnome-flashback (metacity).

(These interruptions can also be triggered by scanning for access points, like when viewing wifi settings or using the wifi chooser in the taskbar. In this case, the interruptions are simultaneous to the list of networks updating, every 15 seconds or so. This is consistent across all 3 desktop environments.)

My complaint is specific to the interruptions every 303 seconds; I don't mind having network blips while switching wifi settings, and that's not Regolith-specific.

To Reproduce

1. Get laptop with wifi card rtl8821ce
2. Install Ubuntu 20.10,
3. Install/enable the rtl8821ce-dkms wifi driver.
4. Install regolith-complete from PPA
5. Log into regolith
6. Open terminal. Start pinging the router's IP address, filtering out pings of <500 ms and prepending timestamps: ping 192.168.1.1 | grep --line-buffered -E 'time=([0-9]{4}|[5-9][0-9]{2})' | ts '[%H:%M:%S]'
7. Wait at least 10 minutes in order to see the 303 second interval between two blips.

Here is my output:

> $ ping 192.168.1.1 | grep --line-buffered -E 'time=([0-9]{4}|[5-9][0-9]{2})' | ts '[%H:%M:%S]'
[12:37:27] 64 bytes from 192.168.1.1: icmp_seq=279 ttl=64 time=3205 ms
[12:37:27] 64 bytes from 192.168.1.1: icmp_seq=280 ttl=64 time=2178 ms
[12:37:27] 64 bytes from 192.168.1.1: icmp_seq=281 ttl=64 time=1155 ms
[12:42:31] 64 bytes from 192.168.1.1: icmp_seq=582 ttl=64 time=3223 ms
[12:42:31] 64 bytes from 192.168.1.1: icmp_seq=583 ttl=64 time=2199 ms
[12:42:31] 64 bytes from 192.168.1.1: icmp_seq=584 ttl=64 time=1175 ms
[12:47:35] 64 bytes from 192.168.1.1: icmp_seq=885 ttl=64 time=3228 ms
[12:47:35] 64 bytes from 192.168.1.1: icmp_seq=886 ttl=64 time=2211 ms
[12:47:35] 64 bytes from 192.168.1.1: icmp_seq=887 ttl=64 time=1187 ms
[12:52:39] 64 bytes from 192.168.1.1: icmp_seq=1188 ttl=64 time=3221 ms
[12:52:39] 64 bytes from 192.168.1.1: icmp_seq=1189 ttl=64 time=2211 ms
[12:52:39] 64 bytes from 192.168.1.1: icmp_seq=1190 ttl=64 time=1187 ms
[12:57:43] 64 bytes from 192.168.1.1: icmp_seq=1491 ttl=64 time=3601 ms
[12:57:43] 64 bytes from 192.168.1.1: icmp_seq=1492 ttl=64 time=2590 ms
[12:57:43] 64 bytes from 192.168.1.1: icmp_seq=1493 ttl=64 time=1566 ms
[12:57:43] 64 bytes from 192.168.1.1: icmp_seq=1494 ttl=64 time=542 ms
[13:02:47] 64 bytes from 192.168.1.1: icmp_seq=1794 ttl=64 time=3824 ms
[13:02:47] 64 bytes from 192.168.1.1: icmp_seq=1795 ttl=64 time=2814 ms
[13:02:47] 64 bytes from 192.168.1.1: icmp_seq=1796 ttl=64 time=1790 ms
[13:02:47] 64 bytes from 192.168.1.1: icmp_seq=1797 ttl=64 time=766 ms
[13:07:52] 64 bytes from 192.168.1.1: icmp_seq=2098 ttl=64 time=3054 ms
[13:07:52] 64 bytes from 192.168.1.1: icmp_seq=2099 ttl=64 time=2042 ms
[13:07:52] 64 bytes from 192.168.1.1: icmp_seq=2100 ttl=64 time=1018 ms
[13:12:57] 64 bytes from 192.168.1.1: icmp_seq=2401 ttl=64 time=3545 ms
[13:12:57] 64 bytes from 192.168.1.1: icmp_seq=2402 ttl=64 time=2530 ms
[13:12:57] 64 bytes from 192.168.1.1: icmp_seq=2403 ttl=64 time=1506 ms
[13:16:51] 64 bytes from 192.168.1.1: icmp_seq=2637 ttl=64 time=1029 ms
[13:18:00] 64 bytes from 192.168.1.1: icmp_seq=2704 ttl=64 time=3620 ms
[13:18:00] 64 bytes from 192.168.1.1: icmp_seq=2705 ttl=64 time=2599 ms
[13:18:00] 64 bytes from 192.168.1.1: icmp_seq=2706 ttl=64 time=1575 ms
[13:18:00] 64 bytes from 192.168.1.1: icmp_seq=2707 ttl=64 time=551 ms
[13:23:04] 64 bytes from 192.168.1.1: icmp_seq=3007 ttl=64 time=3899 ms
[13:23:04] 64 bytes from 192.168.1.1: icmp_seq=3008 ttl=64 time=2887 ms
[13:23:04] 64 bytes from 192.168.1.1: icmp_seq=3009 ttl=64 time=1863 ms
[13:23:04] 64 bytes from 192.168.1.1: icmp_seq=3010 ttl=64 time=839 ms

Expected behavior The expected result, and what I see when logging into Ubuntu or gnome-flashback, is empty output after 30 minutes of pinging, because every ping is faster than the filter threshold.

Installation Details

• Regolith Install Type: PPA
• Regolith Version: regolith-desktop-complete/groovy,now 2.109-1groovy amd64
• PPA url: [default: ppa:regolith-linux/release]
• Host OS (for PPA): Ubuntu 20.10

Additional context The fact that this seems to be a network process on a 5 minute timer should narrow things down, but I haven't been able to identify/kill the responsible process.

I did ps aux in both gnome-flashback and regolith, and diffed the outputs to see exactly what processes could be responsible. Then I tried pkill on a variety of regolith-specific things, waiting to see if it resolved the 5 minute interval blips, then continuing:

pkill i3xrocks: did not resolve
killing gsd-wwan: did not resolve
killing rofi: did not resolve
pkill update-notifier: did not resolve
pkill i3bar: did not resolve
pkill nm-applet: did not resolve

Unfortunately, killing all of these did not stop the blips.

I've tried disabling network manager's Connectivity Checking setting to no noticeable effect.

I've checked dmesg and network manager logs, but don't see any messages corresponding to the blips.

This is only a minor problem for me, but any suggestions for other ways to diagnose this are welcome!