Comment 8 for bug 984552

I noticed this problem in 11.10. My wifi worked great in 11.04, but as soon as I migrated to 11.10, my wifi became unbearably slow. Running iwconfig, I noticed that the "TX excessive retries" was incrementing like crazy when browsing the web:

ubuntu@ubuntu:~$ iwconfig
lo no wireless extensions.

eth0 no wireless extensions.

wlan0 IEEE 802.11bgn ESSID:"Wolfy"
          Mode:Managed Frequency:2.462 GHz Access Point: 00:22:6B:7E:65:87
          Bit Rate=72.2 Mb/s Tx-Power=14 dBm
          Retry long limit:7 RTS thr:off Fragment thr:off
          Power Management:off
          Link Quality=70/70 Signal level=-29 dBm
          Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
          Tx excessive retries:179 Invalid misc:54 Missed beacon:0

ubuntu@ubuntu:~$ iwconfig
lo no wireless extensions.

eth0 no wireless extensions.

wlan0 IEEE 802.11bgn ESSID:"Wolfy"
          Mode:Managed Frequency:2.462 GHz Access Point: 00:22:6B:7E:65:87
          Bit Rate=72.2 Mb/s Tx-Power=14 dBm
          Retry long limit:7 RTS thr:off Fragment thr:off
          Power Management:off
          Link Quality=70/70 Signal level=-29 dBm
          Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
          Tx excessive retries:251 Invalid misc:64 Missed beacon:0

I disabled N-mode wifi using:

root@ubuntu:~# echo "options iwlagn 11n_disable=1" > /etc/modprobe.d/iwlagn.conf

root@ubuntu:~# modprobe -v iwlagn
insmod /lib/modules/3.0.0-12-generic/kernel/net/wireless/cfg80211.ko
insmod /lib/modules/3.0.0-12-generic/kernel/net/mac80211/mac80211.ko
insmod /lib/modules/3.0.0-12-generic/kernel/drivers/net/wireless/iwlwifi/iwlagn.ko 11n_disable=1

Running iwconfig then showed no TX retries.

root@ubuntu:~# iwconfig
lo no wireless extensions.

eth0 no wireless extensions.

wlan1 IEEE 802.11bg ESSID:"Wolfy"
          Mode:Managed Frequency:2.462 GHz Access Point: 00:22:6B:7E:65:87
          Bit Rate=2 Mb/s Tx-Power=14 dBm
          Retry long limit:7 RTS thr:off Fragment thr:off
          Encryption key:off
          Power Management:off
          Link Quality=70/70 Signal level=-31 dBm
          Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
          Tx excessive retries:0 Invalid misc:41 Missed beacon:0

Under 12.04, though, I'm seeing a lot of "Invalid misc" retries.
I was really hoping that under 12.04 that this issue would be fixed. BTW, this is on an Acer AspireOne netbook model AOD255E-13695.

Could this be router-related? I am using a Cisco WRT160N.

Bruce