iwlwifi kernel driver does not obey power saving settings

[Jason Straight]

Poor ping times (high latency) can be observed after unplugging from a power source.

To recreate this issue start by disabling power saving and hw encryption while your laptop is plugged in.

Power saving can be turned off at module load time, or with iwconfig [dev] power off

rmmod iwldvm iwlwifi && modprobe iwlwifi power_save=0 swcrypto=1 power_level=1

Will remove the driver and re-insert with power saving off and sw encryption on.

start a ping to your router

Watch latency; should be 3ms or so.

Unplug laptop from power and watch latency rise to 60+ ms

To get reliable networking again, either plug laptop back in or re-issue commands to disable power saving.

Changing the power state of the machine changes the power state of the nic regardless of setting. What I've found is that setting power saving to on/off puts the card in power saving state instead of disabling or enabling based on power source.

If you unplug your machine you must re-issue the commands to disable power saving.

ProblemType: Bug
DistroRelease: Ubuntu 13.10
Package: linux-image-extra-3.11.0-12-generic 3.11.0-12.19
ProcVersionSignature: Ubuntu 3.11.0-12.19-generic 3.11.3
Uname: Linux 3.11.0-12-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.12.5-0ubuntu2.1
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC1: junfan 2247 F.... pulseaudio
 /dev/snd/controlC0: junfan 2247 F.... pulseaudio
Date: Thu Nov 7 11:20:09 2013
InstallationDate: Installed on 2013-10-19 (19 days ago)
InstallationMedia: Kubuntu 13.10 "Saucy Salamander" - Release amd64 (20131016.1)
MachineType: LENOVO 20193
MarkForUpload: True
ProcFB:

ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-3.11.0-12-generic root=UUID=dfae3dc5-7847-4e9e-a98c-b4ca8ef075a2 ro quiet splash
RelatedPackageVersions:
 linux-restricted-modules-3.11.0-12-generic N/A
 linux-backports-modules-3.11.0-12-generic N/A
 linux-firmware 1.116
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 02/08/2013
dmi.bios.vendor: LENOVO
dmi.bios.version: 6BCN42WW(V2.02)
dmi.board.asset.tag: No Asset Tag
dmi.board.name: INVALID
dmi.board.vendor: LENOVO
dmi.board.version: 31900003WIN8 STD MLT
dmi.chassis.asset.tag: No Asset Tag
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: Lenovo IdeaPad Y500
dmi.modalias: dmi:bvnLENOVO:bvr6BCN42WW(V2.02):bd02/08/2013:svnLENOVO:pn20193:pvrLenovoIdeaPadY500:rvnLENOVO:rnINVALID:rvr31900003WIN8STDMLT:cvnLENOVO:ct10:cvrLenovoIdeaPadY500:
dmi.product.name: 20193
dmi.product.version: Lenovo IdeaPad Y500
dmi.sys.vendor: LENOVO

[Jason Straight (jason-jeetkunedomaster)]

Maybe this is the intended method for this?

The best fix for the horrid performance this causes is to create a file in /etc/pm/power.d/ containing the "iwconfig wlan0 power off" command.

[Brad Figg (brad-figg)]

This change was made by a bot.

[Joseph Salisbury (jsalisbury)]

Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v3.12 kernel[0].

If this bug is fixed in the mainline kernel, please add the following tag 'kernel-fixed-upstream'.

If the mainline kernel does not fix this bug, please add the tag: 'kernel-bug-exists-upstream'.

If you are unable to test the mainline kernel, for example it will not boot, please add the tag: 'kernel-unable-to-test-upstream'.
Once testing of the upstream kernel is complete, please mark this bug as "Confirmed".

Thanks in advance.

[0] http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.12-saucy/

[Launchpad Janitor (janitor)]

[Expired for linux (Ubuntu) because there has been no activity for 60 days.]

[camden lindsay (camden-lindsay+launchpad)]

Currently still a problem with [dylan@zenbook ~]$ uname -a
Linux zenbook 3.12.6-1-iwlwifidebug #1 SMP PREEMPT Sun Dec 29 01:49:34 PST 2013 x86_64 GNU/Linux

Email sent to 'support' addresses listed on kernel iwlwifi page (http://wireless.kernel.org/en/users/Drivers/iwlwifi)

[ConceptRat (conceptrat)]

If you're using TLP http://linrunner.de/en/tlp/tlp.html then you can disable power management when on battery by changing the option "WIFI_PWR_ON_BAT=5" to "WIFI_PWR_ON_BAT=1" about halfway down in the file "/etc/default/tlp".