[ath9k] AR5008/AR5416 802.11n wireless card performs very slowly

[Aaron Kelley]

Using Ubuntu 8.10.

I have a wireless card with the Atheros AR5008 chipset (802.11n), and it uses the ath9k driver. The performance of this card in Ubuntu is terrible.

On an 802.11n network, where I often connect in Windows or OS X at a reported speed of 130 mbps (with none of these speed issues); iwconfig in Ubuntu reports that I am connected at 1 mbps. I do not know if the information iwconfig is presenting is accurate, however, there is a noticeable drop in the speed of local transfers (i.e., transferring files over a LAN is very slow, controlling a machine via VNC crawls). Switching to a 100 mbps resolves all speed issues, when the difference shouldn't be that noticeable.

[Aaron Kelley (aaronkelley)]

Clarification:
> Switching to a 100 mbps resolves all speed issues, when the difference shouldn't be that noticeable.
I meant using a wired connection here. :-P

[Aaron Kelley (aaronkelley)]

Notes:

I tried a current snapshot of ath9k from wireless.kernel.org:
http://wireless.kernel.org/en/users/Download
(The snapshot I tested was dated November 10, 2008.)

Transfer speeds were much improved with this snapshot. This makes me hopeful that a fixed version of the driver will eventually make its way into the kernel.

However, I got a kernel panic while using it so I do not think it is quite ready yet. :-P

Numbers:
With the stock version of ath9k (included with Ubuntu) I get about 220 KB/sec transferring from an FTP server running on my LAN.
With the updated version from wireless.kernel.org the speed is up a little over 3 MB/sec (about what I'd expect).

[Salvador Diaz (salvadordiaz)]

I can confirm I'm having the same issues on a Macbook Pro 2,2 , which has a wireless card with the exact same chipset (AR5008). I can confirm also that I'm having the same problem described in this bug report: https://bugs.edge.launchpad.net/ubuntu/+source/linux/+bug/278190

Relevant output from lspci:
03:00.0 Network controller: Atheros Communications Inc. AR5008 Wireless Network Adapter (rev 01)

Relevant output from modinfo ath9k:
filename: /lib/modules/2.6.27-9-generic/kernel/drivers/net/wireless/ath9k/ath9k.ko
srcversion: 5307204F68EC6FC867B1E91
depends: mac80211
vermagic: 2.6.27-9-generic SMP mod_unload modversions 586

As the other bug report doesn't relate to this hardware, I'll just report here my findings.

I was having intermittent disconnections so I thought I'd try the workaround proposed for bug #278190: turning off encryption, but my ISP (which controls the router) won't let me have an open access point, so I just changed the encryption from WPA(TKIP+AES) to WPA(TKIP) and since then I haven't had any disconnections.

Relevant output from dmesg with my router in WPA(TKIP+AES) mode:
[ 59.852468] wlan0: authenticate with AP 62:7a:0d:84:8c:60
[ 60.052093] wlan0: authenticate with AP 62:7a:0d:84:8c:60
[ 60.252121] wlan0: authenticate with AP 62:7a:0d:84:8c:60
[ 60.453073] wlan0: authentication with AP 62:7a:0d:84:8c:60 timed out
[ 79.344353] wlan0: authenticate with AP 62:7a:0d:84:8c:60
[ 79.344464] wlan0: authenticate with AP 62:7a:0d:84:8c:60
[ 79.544073] wlan0: authenticate with AP 62:7a:0d:84:8c:60
[ 79.744070] wlan0: authenticate with AP 62:7a:0d:84:8c:60
[ 79.944074] wlan0: authentication with AP 62:7a:0d:84:8c:60 timed out

Relevant output from dmesg with my router in WPA(TKIP) mode:
[ 98.988339] wlan0: authenticate with AP 62:7a:0d:84:8c:60
[ 98.990516] wlan0: authenticated
[ 98.990525] wlan0: associate with AP 62:7a:0d:84:8c:60
[ 99.000239] wlan0: RX AssocResp from 62:7a:0d:84:8c:60 (capab=0x411 status=0 aid=2)
[ 99.000251] wlan0: associated
[ 99.000677] wlan0 (WE) : Wireless Event too big (338)
[ 99.008113] ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready