I just upgraded from Ubuntu 18.04 to 20.04 on one of the Dell XPS 13 machines, and the network performance is abhorrent. Internet speed is very fast from a google speed test (>300Mb/s for both upload and download).
However, whenever I try to browse a website or even run
sudo apt update the connection will often time out. My internet is very fast on all other devices and I really don't know how to debug this problem.
sudo lshw -class network -short && nmcli device status
H/W path Device Class Description ============================================================== /0/100/1c.6/0 wlp2s0 network Wi-Fi 6 AX200 /3 br-96f5b790e29e network Ethernet interface /4 br-15e76fb81c05 network Ethernet interface /5 docker0 network Ethernet interface DEVICE TYPE STATE CONNECTION wlp2s0 wifi connected CSA HQ br-15e76fb81c05 bridge connected br-15e76fb81c05 br-96f5b790e29e bridge connected br-96f5b790e29e docker0 bridge connected docker0 p2p-dev-wlp2s0 wifi-p2p disconnected -- lo loopback unmanaged -- gpd0 tun unmanaged --
It seems like this is a pretty common problem, and one without a definitive cause. For me, it was because Ubuntu resets the TLP configuration, and the power management went back to "on". I disabled wifi power management directly by editing:
sudo nano /etc/NetworkManager/conf.d/default-wifi-powersave-on.conf
Then changed the value from 3 to 2, saved changes and rebooted.
I actually got this solution from Reddit and this worked for my case specifically but it seems like it could be caused by a bunch of other things. Read all the proposed solutions below!