Linux Wi-Fi power saving

I'm on Endeavor OS (recommend, except switch theme to default), and recently, I noticed that if I ping google, I get sort-of ladder of ping times:

$ ping 8.8.8.8                       
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
64 bytes from 8.8.8.8: icmp_seq=1 ttl=57 time=15.8 ms
64 bytes from 8.8.8.8: icmp_seq=2 ttl=57 time=21.4 ms
64 bytes from 8.8.8.8: icmp_seq=3 ttl=57 time=85.6 ms
64 bytes from 8.8.8.8: icmp_seq=4 ttl=57 time=41.0 ms
64 bytes from 8.8.8.8: icmp_seq=5 ttl=57 time=28.4 ms
64 bytes from 8.8.8.8: icmp_seq=6 ttl=57 time=50.7 ms
64 bytes from 8.8.8.8: icmp_seq=7 ttl=57 time=72.7 ms
64 bytes from 8.8.8.8: icmp_seq=8 ttl=57 time=94.6 ms
64 bytes from 8.8.8.8: icmp_seq=9 ttl=57 time=117 ms

See how it rises up? That was very weird. At some points the ping would even timeout. Similar effect would be noticeable in voice calls or games. Eventually, I found out that it was power_save.

Even though I'm on a PC, not a laptop, power saving was still enabled (and it is enabled by default in most distros it seems) in NetworkManager.

To check if you have it enabled or disabled you need to run:

sudo iw dev wlan0 get power_save

It'll report Power save: on if it's enabled.

But, I didn't have iw installed, so I had to first do yay iw (consult your distro for appropriate installation instructions).

To then disable it, you need to run:

sudo iw dev wlan0 set power_save off

Changes are applied immediately, so, getting it again, you should see Power save: off. And the ping test reports:

$ ping 8.8.8.8                        
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
64 bytes from 8.8.8.8: icmp_seq=1 ttl=57 time=16.2 ms
64 bytes from 8.8.8.8: icmp_seq=2 ttl=57 time=15.9 ms
64 bytes from 8.8.8.8: icmp_seq=3 ttl=57 time=15.7 ms
64 bytes from 8.8.8.8: icmp_seq=4 ttl=57 time=16.2 ms
64 bytes from 8.8.8.8: icmp_seq=5 ttl=57 time=15.9 ms

Much better. But, changes are not persistent. Appropriate googling terms will probably get you How to turn off Wireless power management permanently on unix.stackexchange, with a bunch of solutions, and I liked one of them the most:

  1. Open /etc/NetworkManager/conf.d/default-wifi-powersave-on.conf
  2. add/modify it so that wifi.powersave is 2:
[connection]
wifi.powersave = 2

Thanks, @Niko!

That's it, reboot and everything is cool.