WiFi not working well, Intel Corporation Cannon Lake PCH CNVi WiFi

Ask Fedora
, ,
1

Hi.
I just switched from Gentoo to Fedora.
On Gentoo everything worked fine, just wanted to switch to Fedora.
I have

uname -a
Linux fedora 6.9.12-200.fc40.x86_64 #1 SMP PREEMPT_DYNAMIC Sat Jul 27 15:56:15 UTC 2024 x86_64 GNU/Linux

grep -i pretty /etc/os-release
PRETTY_NAME=“Fedora Linux 40 (Workstation Edition)”

$ lspci|grep -i wifi
00:14.3 Network controller: Intel Corporation Cannon Lake PCH CNVi WiFi (rev 10)

I found from internet that i have to switch off the power savinf of the wifi, so i did that with the command:

sudo iw dev wlo1 set power_save off

But it didn’t help much. now i can use the internet, but it is VERY slow.

At same time i can use the internet fast on another device, another laptop (with different hardware, but a linux distro also)

So it was fast on Gentoo with the same hardware,

Any ideas?

2

Could you provide some context for “slow?”

3

Maybe the driver?

4

Slow means it takes a minute to load this page for example. It is frustrating to wait for pages to open.

ping -f to any destination gives me around 23.1317% packet loss.

The driver? Yes, i know, but how do i fix it? And how do i set the power save mode off by default? Now i have to turn the power save off every time i boot up the laptop.

5

Yikes…

It seems there are a variety of ways to automatically turn off power save mode at boot, like this method or this one; I can’t say which is “better.”

As for the driver, perhaps this page can help…

6

none of these was necessary in Gentoo.
I did not need to switch the driver power save mode off and the firmware was working fine.

I checked and:

dmesg | grep iwlwifi | grep -i firmware
[ 6.935189] iwlwifi 0000:00:14.3: loaded firmware version 46.7e3e4b69.0 9000-pu-b0-jf-b0-46.ucode op_mode iwlmvm

So the firmware is loaded.
But the network is slow anyhow.
Could it be wrong firmware?

btw… while adding a response here, it several times tells me i have another place where i am editing the same post… but i do not have.
(Could be due to network problems also)

7

I believe I have the same adapter (same rev 10 Cannon Lake):

sudo dmesg | grep 9560
[    6.078187] iwlwifi 0000:00:14.3: Detected Intel(R) Wireless-AC 9560 160MHz, REV=0x312

sudo dmesg | grep iwlwifi | grep -i firmware
[    5.726553] iwlwifi 0000:00:14.3: loaded firmware version 46.7e3e4b69.0 9000-pu-b0-jf-b0-46.ucode op_mode iwlmvm

I haven’t noticed any oddities with performance between Windows and Linux; was transferring stuff from my NAS last night and seemed to get around the same 60-70 MB/s speeds.

Here’s what I get with ping -f google.com -i 0.002 -w 10:

ping -f google.com -i 0.002 -w 10
PING google.com (2607:f8b0:4004:c09::66) 56 data bytes
....        
--- google.com ping statistics ---
1264 packets transmitted, 1260 received, 0.316456% packet loss, time 9999ms
rtt min/avg/max/mdev = 22.380/32.377/105.316/5.097 ms, pipe 12, ipg/ewma 7.917/32.809 ms

Did you test wifi speeds on LAN in-case it’s something related to WAN?

8

no, it has nothing to do with WAN, and yes, i tried ping -f 192.168.0.1
it also gives me over 10% packet loss.
But the strange thing is that it will not always do that, so it sometimes works fine and then after 10 min not anymore and maybe again it works in a while…
And all the time i have power saving off

9

My WiFi router has 2 wifi signals, one 5GHz and the other one is 2.5GHz
Tried switching to the 2.5GHz and it seems to work so far. Will report later if it fails.

10

I wonder if it could be different wireless channels? I have a TP-Link AX1500 and use 157 on 5GHz

11

Another thought… Could it be related to an IPv6 issue? You could disable IPv6 and see…

12

Thanks, but it is not IPv6 issue. All have worked fine now with the 2.5 GHz. But i would like to get the 5GHz also to work.

And yes, it is a different channel for 5GHz and 2.5GHz, if i understood correctly.

The 2.5GHz and 5GHz are on the same router, 100% same configuration except the frequency.

13

Interesting… Have you fiddled with things like channel selection? Is the router firmware up-to-date?

14

I’d try a different high 5GHz channel in-case it’s something like DFS or crowded frequency, or maybe the driver on the router or Linux not handling a particular channel well. 153-157 in the US seems ideal.

15

The router i have, is owned by the ISP, and i can’t configure it.
But it works fine with 5GHz in Windows (on the samae machine that i have the problem with fedora) and with my Android phone.

16

That is really frustrating… Can you share the output of ifconfig?

17

I just switched to the 5GHz line (after using the 2.5GH for hours)
and i ran some heavy downloads and uploads and so on…
and this is what i got:
If this is what you mean, here is the ifconfig for the wifi:

wlo1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.0.114 netmask 255.255.255.0 broadcast 192.168.0.255
inet6 fe80::faa2:d39:df92:7c6c prefixlen 64 scopeid 0x20
ether aa:a7:09:e5:bc:a4 txqueuelen 1000 (Ethernet)
RX packets 1353279 bytes 1527223268 (1.4 GiB)
RX errors 0 dropped 2 overruns 0 frame 0
TX packets 543295 bytes 401019609 (382.4 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

18

Thanks for that… The dropped 2 in line six stands out a bit because I don’t think I’ve ever seen anything by a “0” in there on my system.

Sadly, I don’t know enough about networking to be much help. I did, however, come across this in my looking around and it would seem there could be any number of things causing those dropped packets.

When you switched from the 2.4 to the 5, was your speed still noticeably slower?

19

I’ve encountered problems running linux in computer labs configured for Windows WiFi. There was some Windows-specific configuration that resulted in very low priority and lots of dropped packets for linux until it was reconfigured.
If you can’t tweak the configuration you might consider adding your own WiFi access point (WAP) and POE “hat”. Some WAP examples. My home has several WiFI access points – . the ISP’s router is only needed as backup during power outages when it gets priority for UPS power over the added gear that needs a wired connection to the ISP’s router.

20

well. The speed dropped a bit (not much) with speedtest.net but the speedtest.net site took about 2 minutes to load, when i switch from 2.5GHz to 5GHz
but i am happy with my 2.5GHz for now.