Wireless speed capped?

R

ryanvade

Guest
Hello. I have a question about wireless speed. I am using a new Intel 7260 wireless AC nic. In windows the connection speed to my Netgear R6300v2 router is usually above 400 Mb/s. However, in Linux the speed NEVER goes above 150 Mb/s. What could be causing that? Is it possible that NetworkManager is capping the connection speed? I would not think so, but I have no idea. I am using kernel 3.11-rc2 with the newest firmware. The distribution is Diamond II-B.

Does anyone have any suggestions?

Thanks,
ryanvade
 


I think the test your using makes a difference?
When I check my connection with ISP test it shows crazy high speed up and down, but, using independent tests it's around 1/10 the speed
 
True -
I think the test your using makes a difference?
When I check my connection with ISP test it shows crazy high speed up and down, but, using independent tests it's around 1/10 the speed

True..

Try a test with wget to another local machine..
Code:
wget --output-document=/dev/null http://192.168.0.X/blah.iso

See if you get above the 150mb/s number?
 
Sorry for not responding sooner. I setup a ready share on the router. And downloaded a Fedora ISO to /dev/null (no reason to keep a copy on my laptop) The max speed was 12 Mb/s. NetworkManager is reporting a speed of 150 Mb/s still.
 
The speed is definitely not slow..the test you are using must have been showing wrong results..try speedbit.net..i guess that is a good speed checker.
 
So, an odd development. On campus I am getting a wireless a connection (channel 36, 5180 MHz) of 300 mbits/s. When at my house I get a speed of 150 mbits/s at wireless ac. Any ideas?
 
So, an odd development. On campus I am getting a wireless a connection (channel 36, 5180 MHz) of 300 mbits/s. When at my house I get a speed of 150 mbits/s at wireless ac. Any ideas?

Hmm I noticed on my home network. I was getting 150 mbs as well. Could be the provider? You don't use Comcast by any chance do you?
 
It may be that 802.11ac is not well supported as yet by some drivers. It may be stepping down to 802.11n speeds for various reasons such as router configuration.

You should have a look in your router config and temporarily force it to ac speeds instead of allowing it to run in "mixed mode" and then see if the nic can associate with the AP.
 
Here is Windows:
wireless_speed_windows.png


in a second I will upload a snapshot of Network Manager
wireless_speed_linux.png


So, I upgraded network-manager and you can see the results. Power management is disabled also.
 
Last edited:
You can see that iwconfig reports 802.11abgn, instead of 802.11ac

Yet network connections correctly assumes 802.11ac ("WiFi")

You build your own kernels if I recall correctly? Did you ensure that you installed the new kernel firmware for iwlwifi?
 
You can see that iwconfig reports 802.11abgn, instead of 802.11ac

Yet network connections correctly assumes 802.11ac ("WiFi")

You build your own kernels if I recall correctly? Did you ensure that you installed the new kernel firmware for iwlwifi?
Actually, to use my wifi card I had to update the firmware files. My wifi card uses firmware API lvl 7. I upgraded the firmware from
https://git.kernel.org/cgit/linux/kernel/git/firmware/linux-firmware.git/

The firmware for my wireless card is also available here
http://wireless.kernel.org/en/users/Drivers/iwlwifi

and placed it in /lib/firmware.

Perhaps I missed something?
 
Last edited:
I am going to try iwlwifi-next. And I set CONFIG_PREVENT_FIRMWARE_BUILD to =n

Maybe that will fix something...
 
I finally got a response from Intel
Hi,


Sorry for the delay.

I am not sure if the issue is with the driver or with the upper layers. I need to make sure that NetworkManager’s GUI take our rate into account.

Please note that the 11ac rates will be supported in 3.13 only. We just sent a patch that allows the NIC to transmit in 11ac rates - as I said, it will be included in 3.13.

Regarding Rx, you should be able to get 11ac rates.

I’d suggest to run a test and see the speed you actually get and not what the GUI shows. Can you do that?


Thanks,

Emmanuel
 
Based on the information is this thread, my first guess, at least for RX, there is a bug in the driver that handles the high speed packet processing.
i would expect, if the device can handle the rates and it has properly negotiated with router as 802.11ac then the incoming packet handling should not be effected by the linux stack. TX packets are a different story since the kernel meters those based on the driver.

of course this is all conjecture as I have not looked at this driver.
 
Or this really could be Network Manager reporting the speed wrong. Either one seems plausible. I guess I need to keep trying new kernels...
 


Top