Hi,

When I enable the iwlwifi power management feature, my connection freezes,
or is very (very) slow. I get up to 90% of lost packets when pinging a machine
in my LAN, and times up to 8000ms.

If I disable the power management, everything is fine.

According to the wireless-iwl-power.conf configuration file, my chip is supported,
but I see I do not have any /sys/class/net/*/device/power_level file (the interface
is wlan0).
I just see /sys/class/net/wlan0/device/power/wakeup with kernel 2.6.32 and an extra control
file in the same directory with kernel 2.6.35

I have the issue with both kernels (from unstable and experimental).

lspci shows:
02:00.0 Network controller: Intel Corporation Centrino Wireless-N 1000
	Subsystem: Intel Corporation Centrino Wireless-N 1000 BGN
	Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 0, Cache Line Size: 64 bytes
	Interrupt: pin A routed to IRQ 28
	Region 0: Memory at d2500000 (64-bit, non-prefetchable) [size=8K]
	Capabilities: <access denied>
	Kernel driver in use: iwlagn

I haven't seen anything in the logs related to this problem, and I do not know how to try and
debug this.

I would be happy to test anything which might help you or upstream debug this.

Cheers,
Julien

- -- System Information:
Debian Release: squeeze/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (100, 'experimental')
Architecture: amd64 (x86_64)

Kernel: Linux 2.6.32-5-amd64 (SMP w/2 CPU cores)
Locale: LANG=fr_FR.utf8, LC_CTYPE=fr_FR.utf8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages laptop-mode-tools depends on:
ii  lsb-base                      3.2-23.1   Linux Standard Base 3.2 init scrip
ii  psmisc                        22.12-1    utilities that use the proc file s
ii  util-linux                    2.17.2-3.1 Miscellaneous system utilities

Versions of packages laptop-mode-tools recommends:
ii  acpid                         1:2.0.6-1  Advanced Configuration and Power I
ii  ethtool                       1:2.6.34-3 display or change Ethernet device
pn  hal                           <none>     (no description available)
ii  hdparm                        9.27-2.1   tune hard disk parameters for high
ii  net-tools                     1.60-23    The NET-3 networking toolkit
ii  pm-utils                      1.3.0-2    utilities and scripts for power ma
ii  sdparm                        1.02-1     Output and modify SCSI device para
ii  wireless-tools                30~pre9-5  Tools for manipulating Linux Wirel

laptop-mode-tools suggests no packages.

- -- Configuration Files:
/etc/laptop-mode/conf.d/dpms-standby.conf changed:
DEBUG=0
CONTROL_DPMS_STANDBY="0"
BATT_DPMS_STANDBY=300
LM_AC_DPMS_STANDBY=1200
NOLM_AC_DPMS_STANDBY=1200

/etc/laptop-mode/conf.d/ethernet.conf changed:
DEBUG=0
CONTROL_ETHERNET="auto"
BATT_THROTTLE_ETHERNET=1
LM_AC_THROTTLE_ETHERNET=0
NOLM_AC_THROTTLE_ETHERNET=0
THROTTLE_SPEED="slowest"
DISABLE_WAKEUP_ON_LAN=1
ETHERNET_DEVICES="eth0"
DISABLE_ETHERNET_ON_BATTERY=1

/etc/laptop-mode/conf.d/wireless-iwl-power.conf changed:
DEBUG=0
CONTROL_IWL_POWER="0"
IWL_AC_POWER=0
IWL_BATT_POWER=3

/etc/laptop-mode/laptop-mode.conf changed:
ENABLE_LAPTOP_MODE_TOOLS=1
VERBOSE_OUTPUT=0
LOG_TO_SYSLOG=1
DEBUG=0
ENABLE_LAPTOP_MODE_ON_BATTERY=1
ENABLE_LAPTOP_MODE_ON_AC=0
ENABLE_LAPTOP_MODE_WHEN_LID_CLOSED=0
ENABLE_AUTO_MODULES=1
MINIMUM_BATTERY_CHARGE_PERCENT=3
DISABLE_LAPTOP_MODE_ON_CRITICAL_BATTERY_LEVEL=1
HD="/dev/[hs]d[abcdefgh]"
PARTITIONS="auto /dev/mapper/*"
ASSUME_SCSI_IS_SATA=1
LM_BATT_MAX_LOST_WORK_SECONDS=600
LM_AC_MAX_LOST_WORK_SECONDS=360
CONTROL_READAHEAD=1
LM_READAHEAD=3072
NOLM_READAHEAD=128
CONTROL_NOATIME=0
USE_RELATIME=1
CONTROL_HD_IDLE_TIMEOUT=1
LM_AC_HD_IDLE_TIMEOUT_SECONDS=20
LM_BATT_HD_IDLE_TIMEOUT_SECONDS=20
NOLM_HD_IDLE_TIMEOUT_SECONDS=7200
CONTROL_HD_POWERMGMT="auto"
BATT_HD_POWERMGMT=1
LM_AC_HD_POWERMGMT=254
NOLM_AC_HD_POWERMGMT=254
CONTROL_HD_WRITECACHE=1
NOLM_AC_HD_WRITECACHE=1
NOLM_BATT_HD_WRITECACHE=0
LM_HD_WRITECACHE=0
CONTROL_MOUNT_OPTIONS=1
LM_DIRTY_RATIO=60
NOLM_DIRTY_RATIO=40
LM_DIRTY_BACKGROUND_RATIO=1
NOLM_DIRTY_BACKGROUND_RATIO=10
DEF_UPDATE=5
DEF_XFS_AGE_BUFFER=15
DEF_XFS_SYNC_INTERVAL=30
DEF_XFS_BUFD_INTERVAL=1
DEF_MAX_AGE=30
XFS_HZ=100
LM_SECONDS_BEFORE_SYNC=2


- -- no debconf information
iEYEARECAAYFAkx2eHoACgkQIQvyq59x1ElhMwCg0E9Xc2YfwK1Q+qwsz8dBL6jz
C8EAoMXiJO9qOfC5k8z6nuQwbetFo+7Q
=dx7P
-----END PGP SIGNATURE-----

Power Savings is broken on some of the Intel WiFi cards. If your's falls under
the same, please disable Power Savings module in laptop-mode-tools. There is
no date as to when the kernel will fix it.

http://git.kernel.org/?p=linux/kernel/git/stable/linux-2.6.32.y.git;a=commit;h=66c9e44e5740fe9024e3ed02fd66ad6e0e57408f
http://bugzilla.intellinuxwireless.org/show_bug.cgi?id=2125

Le jeudi 26 août 2010 à 20:13:09 (+0530), Ritesh Raj Sarraf a écrit :

Hi,

Thanks for your quick answer!

Thanks for these details.

I am not sure I suffer from the same problem, though disabling the power management
does fix the symptoms.

I do not see the error message stated in the bug report.

# dmesg | grep iwl | grep Err
[13429.565608] iwlagn 0000:02:00.0: Error sending REPLY_ADD_STA: enqueue_hcmd failed: -5
[13429.565638] iwlagn 0000:02:00.0: Error sending REPLY_QOS_PARAM: enqueue_hcmd failed: -5
[13429.565649] iwlagn 0000:02:00.0: Error sending REPLY_RXON_ASSOC: enqueue_hcmd failed: -5
[13429.565653] iwlagn 0000:02:00.0: Error setting RXON_ASSOC (-5)

Cheers,
Julien

contain the permanent disabling of the power save feature.

You might want to report a bug upstream at:
http://bugzilla.intellinuxwireless.org

Ritesh