iwl4965 performance issue

[jems]

Binary package hint: linux-ubuntu-modules-2.6.24-12-generic

Laptop with iwl4965 wireless module. The network bandwidth was around 70 KB/sec when it should have been around 300 KB/sec on a 802.11b AP. The OS is Hardy.

I fIxed the problem by adding "options iwl4965 qos_enable=0" to the file /etc/modprobe.d/iwl4965.

It may be useful to disable the QoS, at least while it affects so much the performance ?

[Martijn Faassen (faassen)]

I'm also using this module (on hardy), and get a different problem. Performance is reasonable, until i start transferring a large file (using rsync or scp, say). Once that is going on, performance of the big transfer seems to drown out or block all other traffic. Trying the qos_enable=0 as suggested doesn't seem to solve it.

[jems (jmonnet)]

As we seem to have different issues, I will give some more information on my hardware.

I use a HP 2510p, and I have a wireless AP cisco aironet 350. With this hardware all my connections were slowed down, until I removed QoS ...

If one needs more information, please ask ! :-)

[Martijn Faassen (faassen)]

I'm not currently near my wireless router, it's one of those Linksys G boxes though I updated the firmware to something open sourcy.

I since found out about this issue:

http://www.intellinuxwireless.org/bugzilla/show_bug.cgi?id=1623

which describes my problems right well. Following comment #9, I downloaded the compat-wireless-2.6 tarball (not the git checkout, wouldn't build out of the box) and installed it. This appears to make my problem go away.

[Thomas Herve (therve)]

I confirm the original problem, and that the mentioned fix removing qos fixed the problem for me.
Before: bandwidth limited to 70 Kb/s
After: normal bandwidth (up to 400 Kb/s on Internet, I didn't test on local network).

The driver is iwl4965, on a Lenovo X61s.

[Martijn Faassen (faassen)]

I wrote in a previous problem that installing the compat-wireless modules made my problems go away. I must now amend that; if they were away they have since then returned.

Again, bandwidth is all right it's just that it squashes out any other bandwidth use when a large file is transferred.

The qos fix didn't work for me last time I tried, but I shall try again..

[Petr Menšík (pihhan)]

It is quite normal to kill all traffic other than huge transfer. I dont think you can do much about it. It does depend on what AP you have got, but turning off qos is against principle what is made for - enable important data (interactive) have preference before not importand (download) data. There might be problem in qos algorithm, but i believe it would never work to download at full speed and still have good connection for other things. I think it is general feature of wifi, not a bug, but a feature.

[Martijn Faassen (faassen)]

On Sun, May 25, 2008 at 2:41 PM, Pihhan <email address hidden> wrote:
> It is quite normal to kill all traffic other than huge transfer. I dont
> think you can do much about it.

It's definitely new behavior to me. I've done big transfers before and
it wouldn't kill off all traffic like this, before upgrading the
laptop to Hardy this problem didn't exist.

[Michael Casadevall (mcasadevall)]

Confirmed for me on Intrepid. I did not have this problem when I used Hardy. Perpahs it is of note, but before upgrading, the WLAN light on my laptop didn't work, now it does. The QOS switch fixed it for me

[rahuljoshi80 (rahuljoshi80)]

I am a linux NewB. So please bear with me.
I have the latest Ubuntu version(8.04 with 2.6.24-19 updates) installed on my toshiba a305 laptop. I also have the iwl4965 driver on my machine. I am having exactly the same problem as mentioned in this ticket/bug report. (using a netgear 802.11b wireless router)
However, i dont have a iwl4965 file in my /etc/modprobe.d directory.
Is there another location where i can find it? I tried to do a locate on iwl4965. I found a iwl4965.ko file...but no iwl4965 file.
Since i could not find the required file..i created a iwl4965 file in the /etc/modprobe.d directory. I restarted the machine after that and my band meter test in firefox still shows me that my connection is way too slow.
PLease help! I REALLY LIKE USING ubuntu! However i am afraid that if i dont get my wireless to be fast enough...its a deal breaker.
-Rahul

[rahuljoshi80 (rahuljoshi80)]

Just as an update. I found an "options" file in the etc/modprobe.d directory. I was very exted when i found this file as this seemed like it would be the place where i would need to put in the options command to disable qos.
I tried adding the following line to the options file:
options iwl4965 qos_enable=0

I restarted the machine after this and i still have low speed on the internet. Please help somebody...please.
-Rahul

[Michael Casadevall (mcasadevall)]

This problem appears to have been fixed in intrepid, qos_enable is no longer needed for full speed.

Maybe installing linux-backports-modules-hardy-generic for you hardy users will fix it.

[jems (jmonnet)]

I am using intrepid right now on this very same laptop. If I use the latest linux-image (2.6.25) I have no X, and I cannot see my wifi network (but I can see some others). For the time being, using intrepid kernel may not be an answer :-(

[Leann Ogasawara (leannogasawara)]

Hi Jems,

Since you are the original bug reporter, is this still an issue with the final release of Intrepid? If the issue still exists, what if you try installing linux-backports-modules-intrepid as it contains and updated compat-wireless stack. For now, I'm going to migrate this bug forward to the actively developed linux kernel. Beginning with the Intrepid release the linux-ubuntu-modules package was merged with the linux kernel package. Thanks.

[jems (jmonnet)]

Hi Leann,

Unfortunately, I can't tell, as I am also a victim of all the intel bugs of Intrepid [1], and I had to go back to hardy . I will try as soon as possible (maybe next weekend ?) to install an intrepid on a new partition

Jeremy

[1] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/286285 and https://bugs.launchpad.net/linux/+bug/276990

[jems (jmonnet)]

Hi Leann,

I tried this on both hardy and intrepid, and this seems to be ok on both (both fresh installs, upgrade done). I am not at home, but I'm trying in very similar conditions (same laptop, same wifi encryption).

I think you may close this bug.

Jérémy

[Leann Ogasawara (leannogasawara)]

Thanks for the update, I'll go ahead and close this out.

[Launchpad Janitor (janitor)]

Per a decision made by the Ubuntu Kernel Team, bugs will longer be assigned to the ubuntu-kernel-team in Launchpad as part of the bug triage process. The ubuntu-kernel-team is being unassigned from this bug report. Refer to https://wiki.ubuntu.com/KernelTeamBugPolicies for more information. Thanks.

[chekhovs1 (chekovs)]

Had the same problem: Ubuntu Jaunty (9.04), Lenovo T400 laptop with Intel 53050AGN. I had slow download speeds when using wireless b (802.11b; ~70 KB/sec) and normal rates for wireless g (802.11g; ~1000 KB/sec).

Solution that worked for me: install the latest wireless drivers package (compat-wireless, http://linuxwireless.org/en/users/Download#Download_latest_Linux_wireless_drivers):

sudo apt-get install linux-backports-modules-intrepid-server

After reboot download speeds became normal.

[ Original post: http://ubuntuforums.org/archive/index.php/t-1032617.html ]

Btw, I could not get to disable the QoS as discussed above (for that you have to rename options to options.conf but iwlang and/or iwl3945 still appeared to use QoS as "modinfo iwl3945" and "modinfo iwlang" showed).

[dmuir (dmuir)]

On Jaunty that should be

sudo apt-get install linux-backports-modules-jaunty

Been having the issue since Hardy and currently with a fresh install of Jaunty. Hoping Karmic will have this fixed, as the backports package fixes the issue for me. But maybe not, since the backports package for intrepid supposedly fixed it too, which means the fixes should have been in Jaunty (unless I'm mistaken).

The issue (from reading similar reports) seems to occur when connected to a b router. Using a g or n router should work fine. That would explain why things were working for Jérémy, but not others. This has been my experience also. I was getting around 600 Kbps on my router (b), but full speed on others.