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kellerman

Member

From: Latvia

Registered: 2011-07-20

Posts: 104

[WORKAROUND]ath9k randomly low latency

Hi. I'm randomly getting low latency (ping) with
03:00.0 Network controller: Atheros Communications Inc. AR9462 Wireless Network Adapter (rev 01)

It looks like this:

30-40 fine ping requests, and then unexpected drops happen.
This happens with core kernel and testing kernel. I even installed compat-drivers-patched with ath9k driver and it didn't help.
With Windows it's fine as well as the internet connection and the router. Maybe there is something more I can try?
Thanks!

Last edited by kellerman (2013-03-27 18:50:28)

elkoraco

Member

Registered: 2013-02-18

Posts: 140

Re: [WORKAROUND]ath9k randomly low latency

Does this help with ath9k?

modprobe -r ath9k
modprobe ath9k nohwcrypt=1

kellerman

Member

From: Latvia

Registered: 2011-07-20

Posts: 104

Re: [WORKAROUND]ath9k randomly low latency

I remember trying this a long time ago when there were slimilar problems (with random disconnecting if remember correctly).
The results with nohwcrypt=1 :
Gnome Networkmanager sees networks, but cant connect. Using wifi-menu and wpa_supplicant I can connect, but the connection drops after a while, don't know why (the module seems to crash the wireless, the wi-fi led blanks out).
dmesg outputs this (makes no sense to me):

[ 1248.679771] wlan0: authenticate with 74:ea:3a:c2:1d:54
[ 1248.689798] wlan0: capabilities/regulatory prevented using AP HT/VHT configuration, downgraded
[ 1248.694362] wlan0: send auth to 74:ea:3a:c2:1d:54 (try 1/3)
[ 1248.696402] wlan0: authenticated
[ 1253.690560] wlan0: deauthenticating from 74:ea:3a:c2:1d:54 by local choice (reason=3)
[ 1261.007266] ath9k: ath9k: Driver unloaded
[ 1261.782824] Compat-drivers backport release: compat-drivers-v3.8-1-u
[ 1261.782827] Backport based on linux.git v3.8
[ 1261.782827] compat.git: linux.git
[ 1261.789109] cfg80211: Calling CRDA to update world regulatory domain
[ 1261.811896] ath: phy0: ASPM enabled: 0x42
[ 1261.811899] ath: EEPROM regdomain: 0x6c
[ 1261.811900] ath: EEPROM indicates we should expect a direct regpair map
[ 1261.811902] ath: Country alpha2 being used: 00
[ 1261.811903] ath: Regpair used: 0x6c
[ 1261.812455] ieee80211 phy0: Selected rate control algorithm 'ath9k_rate_control'
[ 1261.812827] ieee80211 phy0: Atheros AR9462 Rev:2 mem=0xffffc90024f00000, irq=17
[ 1269.799265] ath9k: ath9k: Driver unloaded
[ 1271.600595] Compat-drivers backport release: compat-drivers-v3.8-1-u
[ 1271.600598] Backport based on linux.git v3.8
[ 1271.600599] compat.git: linux.git
[ 1271.606981] cfg80211: Calling CRDA to update world regulatory domain
[ 1271.630034] ath: phy0: ASPM enabled: 0x42
[ 1271.630038] ath: EEPROM regdomain: 0x6c
[ 1271.630038] ath: EEPROM indicates we should expect a direct regpair map
[ 1271.630040] ath: Country alpha2 being used: 00
[ 1271.630041] ath: Regpair used: 0x6c
[ 1271.630560] ieee80211 phy0: Selected rate control algorithm 'ath9k_rate_control'
[ 1271.630904] ieee80211 phy0: Atheros AR9462 Rev:2 mem=0xffffc90024d80000, irq=17
[ 1293.775026] ath9k: ath9k: Driver unloaded
[ 1295.727194] Compat-drivers backport release: compat-drivers-v3.8-1-u
[ 1295.727197] Backport based on linux.git v3.8
[ 1295.727197] compat.git: linux.git
[ 1295.733560] cfg80211: Calling CRDA to update world regulatory domain
[ 1295.756580] ath: phy0: ASPM enabled: 0x42
[ 1295.756583] ath: EEPROM regdomain: 0x6c
[ 1295.756584] ath: EEPROM indicates we should expect a direct regpair map
[ 1295.756586] ath: Country alpha2 being used: 00
[ 1295.756586] ath: Regpair used: 0x6c
[ 1295.757116] ieee80211 phy0: Selected rate control algorithm 'ath9k_rate_control'
[ 1295.757395] ieee80211 phy0: Atheros AR9462 Rev:2 mem=0xffffc90024e80000, irq=17

maybe I should remove compat-drivers-patched with patched ath9k driver?

EDIT: I removed that driver and added "options ath9k nohwcrypt=1" (and did a reboot) to ath9k.conf at /etc/modprobe.d
still no luck...

Last edited by kellerman (2013-03-08 16:11:17)

elkoraco

Member

Registered: 2013-02-18

Posts: 140

Re: [WORKAROUND]ath9k randomly low latency

If you go without the compat drivers, and want aht9k to load without hwcrypt, your /etc/modprobe.d/ath9k.conf should look like this

options ath9k nohwcrypt=1

kellerman

Member

From: Latvia

Registered: 2011-07-20

Posts: 104

Re: [WORKAROUND]ath9k randomly low latency

yeah, I made a typo in the post, still no luck

[km@acer-laptop modprobe.d]$ cat ath9k.conf
options ath9k nohwcrypt=1

and I tried it without the compat drivers this time

Last edited by kellerman (2013-03-08 11:34:28)

kellerman

Member

From: Latvia

Registered: 2011-07-20

Posts: 104

Re: [WORKAROUND]ath9k randomly low latency

Actually Counter Strike 1.6 runs like a crap with this connection. Then you feel the drops most.

 lspci | grep Atheros
03:00.0 Network controller: Atheros Communications Inc. AR9462 Wireless Network Adapter (rev 01)

dmesg | grep ath9k
[    8.298899] ieee80211 phy0: Selected rate control algorithm 'ath9k_rate_control'
[14648.797653] ath9k 0000:03:00.0 wlan0: disabling HT as WMM/QoS is not supported by the AP
[14648.797657] ath9k 0000:03:00.0 wlan0: disabling VHT as WMM/QoS is not supported by the AP
[16271.131031] ath9k 0000:03:00.0 wlan0: disabling HT as WMM/QoS is not supported by the AP
[16271.131034] ath9k 0000:03:00.0 wlan0: disabling VHT as WMM/QoS is not supported by the AP

EDIT:
I'm now trying ath9k from kernel v3.9-rc1 to see if there are any changes.
I wasn't successful with disabling ani as can be seen here https://bbs.archlinux.org/viewtopic.php?id=158924 in the 2nd post. This might be the same issue
EDIT:
drivers from kernel 3.9 shows more signal strenght, but the lags persist. I was unable to enable debug for them.

Last edited by kellerman (2013-03-08 17:35:12)

vyu223

Member

Registered: 2013-02-18

Posts: 24

Re: [WORKAROUND]ath9k randomly low latency

What is your max ping? From the image you posted, it looks like the max for you is around 150 ms. Also, what is the period of high pings (as in, 1/frequency)? The symptoms of the ANI problem is that the ping is around 1000-2000 ms, with the period consistently around 30 seconds. From the first post on this bug report, it is indicated that the lag happens every 30 seconds because of a particular define. The OP says that changing the value of the define changes the frequency of the problem.

But even so, if your symptoms are not that similar, you should be close enough to disabling ANI just to see if it fixes your issue. I'll write a reply to that thread right now.

kellerman

Member

From: Latvia

Registered: 2011-07-20

Posts: 104

Re: [WORKAROUND]ath9k randomly low latency

Yes, it's approximately 150, I agree that the symptoms are not that similar. I'll reply to you in the other thread.

EDIT:
Finnaly seems that the problem doesnt persist if I disable NetworkManager pernamently and reboot, and connect using wifi-menu.
Maybe because of searching for networks all the time.

ANOTHER EDIT:
Now I'm using wicd. Works great!

Last edited by kellerman (2013-03-27 18:51:10)