kworker - defunct and consumes 36% cpu time alone

SUSE Product Topics SLED Hardware
1

OS: SLED 11 SP2 x864
HW: Dell Latitude E5420

Didn’t experience/face the following problem with SLED 11 SP1 i586 on the same HW.

Problem occurs only when:
if notebook is running on AC Power, and battery is not fully(100%) charged

Solution/remedy:
problem gone as soon battery charged 100% or if I disconnect the power, i.e put the system on DC power(on battery)

Problem:
1 - Mouse/Curser start moving very slow… like you are accessing the system via vnc.
2 - ‘top’ shows that ‘kworker’ alone is consuming 36% of cpu constantly

top - 00:38:32 up 59 min,  4 users,  load average: 1.91, 1.57, 0.86
Tasks: 188 total,   1 running, 187 sleeping,   0 stopped,   0 zombie
Cpu(s):  2.7%us,  3.1%sy,  0.0%ni, 92.3%id,  2.0%wa,  0.0%hi,  0.0%si,  0.0%st
Mem:   8085988k total,  2725724k used,  5360264k free,   144076k buffers
Swap:  2096444k total,        0k used,  2096444k free,  2140064k cached

  PID USER      PR  NI  VIRT  RES  SHR S   %CPU %MEM    TIME+  COMMAND                                                                                                 
10669 root      20   0     0    0    0 D     22  0.0   0:56.15 kworker/3:3                                                                                             
10606 root      20   0     0    0    0 S     14  0.0   0:49.80 kworker/1:1                                                                                             
   93 root      20   0     0    0    0 D      4  0.0   0:05.49 kworker/u:5                                                                                             
 2444 root      20   0  132m  25m  11m S      2  0.3   0:54.40 X                                                                                                       
 4630 msharf    20   0  240m  17m  11m S      2  0.2   0:05.26 gnome-terminal                                                                                          
    1 root      20   0 10528  876  744 S      0  0.0   0:02.14 init                                                                                                    
    2 root      20   0     0    0    0 S      0  0.0   0:00.00 kthreadd

3 - ps aux |grep ‘kworker’ shows following root 23153 0.2 0.0 0 0 ? S 12:53 0:03 [kworker/1:2] root 26633 0.1 0.0 0 0 ? S 12:57 0:01 [kworker/3:0] root 26818 8.7 0.0 0 0 ? [COLOR="#FF0000"][B] D[/B][/COLOR] 12:57 1:59 [kworker/2:0] root 27172 0.0 0.0 0 0 ? S 11:59 0:00 [kworker/1:3] root 27402 6.5 0.0 0 0 ? S 12:57 1:26 [kworker/0:1] root 28852 0.0 0.0 0 0 ? S 12:05 0:02 [kworker/1:0] root 92 0.1 0.0 0 0 ? [COLOR="#FF0000"][B]D[/B][/COLOR] 11:35 0:10 [kworker/u:4] root 93 0.3 0.0 0 0 ? S 11:35 0:21 [kworker/u:5] root 4743 0.0 0.0 0 0 ? S 13:06 0:00 [kworker/3:1] root 5759 4.5 0.0 0 0 ? S 12:38 1:52 [kworker/0:3] root 7327 7.3 0.0 0 0 ? S 13:08 0:51 [kworker/2:2] root 12484 0.0 0.0 0 0 ? S 13:12 0:00 [kworker/0:0] root 13891 0.0 0.0 0 0 ? S 13:14 0:00 [kworker/2:1] root 15858 0.0 0.0 0 0 ? S 11:48 0:02 [kworker/3:2] root 16894 0.0 0.0 0 0 ? S 12:48 0:00 [kworker/3:3] root 16926 0.0 0.0 0 0 ? S 12:23 0:01 [kworker/1:1] root 18354 0.0 0.0 0 0 ? S 13:18 0:00 [kworker/0:2]

what should I do ?
I have SLE support… May I open a Bug Report ? how ?
Please help

Regards,
Muhammad Sharfuddin

2

Hi
You can open a bug in bugzilla or an SR (See the NCC page)

On a side note, I see you have two accounts, which one would you
prefer to use and will arrange for the other to be removed.

–
Cheers Malcolm °¿° (Linux Counter #276890)
SUSE Linux Enterprise Desktop 11 (x86_64) Kernel 3.0.13-0.27-default
up 1 day 20:08, 2 users, load average: 0.11, 0.07, 0.06
CPU Intel i5 CPU M520@2.40GHz | Intel Arrandale GPU

3

I just report the bug at http://support.novell.com/additional/bugreport.html?sourceidint=suplnav4a_bug

4

Hi
Do you have the bug reference number?

–
Cheers Malcolm °¿° (Linux Counter #276890)
SUSE Linux Enterprise Desktop 11 (x86_64) Kernel 3.0.13-0.27-default
up 1 day 21:25, 2 users, load average: 0.00, 0.01, 0.05
CPU Intel i5 CPU M520@2.40GHz | Intel Arrandale GPU

5

[QUOTE=malcolmlewis;3658]Hi
Do you have the bug reference number?
[/QUOTE]
No, when I submit no such information was given to me on the web, nor I received any email yet.
But I have just opened the SR# 10755754451

6

I just got the solution at http://www.mail-archive.com/acpi-bugzilla@lists.sourceforge.net/msg31832.html
i.e issue resolved as soon I ran the following command

    echo N > /sys/module/drm_kms_helper/parameters/poll

strange thing here is that this solution/problem was posted/updated in 2010-12-27, while SLED 11 SP2 released in 2012, so how SUSE developers missed/skipped to fix this issue.

Regards,
Muhammad Sharfuddin

[QUOTE=sharfuddin;3639]OS: SLED 11 SP2 x864
HW: Dell Latitude E5420

Didn’t experience/face the following problem with SLED 11 SP1 i586 on the same HW.

Problem occurs only when:
if notebook is running on AC Power, and battery is not fully(100%) charged

Solution/remedy:
problem gone as soon battery charged 100% or if I disconnect the power, i.e put the system on DC power(on battery)

Problem:
1 - Mouse/Curser start moving very slow… like you are accessing the system via vnc.
2 - ‘top’ shows that ‘kworker’ alone is consuming 36% of cpu constantly

top - 00:38:32 up 59 min,  4 users,  load average: 1.91, 1.57, 0.86
Tasks: 188 total,   1 running, 187 sleeping,   0 stopped,   0 zombie
Cpu(s):  2.7%us,  3.1%sy,  0.0%ni, 92.3%id,  2.0%wa,  0.0%hi,  0.0%si,  0.0%st
Mem:   8085988k total,  2725724k used,  5360264k free,   144076k buffers
Swap:  2096444k total,        0k used,  2096444k free,  2140064k cached

  PID USER      PR  NI  VIRT  RES  SHR S   %CPU %MEM    TIME+  COMMAND                                                                                                 
10669 root      20   0     0    0    0 D     22  0.0   0:56.15 kworker/3:3                                                                                             
10606 root      20   0     0    0    0 S     14  0.0   0:49.80 kworker/1:1                                                                                             
   93 root      20   0     0    0    0 D      4  0.0   0:05.49 kworker/u:5                                                                                             
 2444 root      20   0  132m  25m  11m S      2  0.3   0:54.40 X                                                                                                       
 4630 msharf    20   0  240m  17m  11m S      2  0.2   0:05.26 gnome-terminal                                                                                          
    1 root      20   0 10528  876  744 S      0  0.0   0:02.14 init                                                                                                    
    2 root      20   0     0    0    0 S      0  0.0   0:00.00 kthreadd

3 - ps aux |grep ‘kworker’ shows following root 23153 0.2 0.0 0 0 ? S 12:53 0:03 [kworker/1:2] root 26633 0.1 0.0 0 0 ? S 12:57 0:01 [kworker/3:0] root 26818 8.7 0.0 0 0 ? [COLOR="#FF0000"][B] D[/B][/COLOR] 12:57 1:59 [kworker/2:0] root 27172 0.0 0.0 0 0 ? S 11:59 0:00 [kworker/1:3] root 27402 6.5 0.0 0 0 ? S 12:57 1:26 [kworker/0:1] root 28852 0.0 0.0 0 0 ? S 12:05 0:02 [kworker/1:0] root 92 0.1 0.0 0 0 ? [COLOR="#FF0000"][B]D[/B][/COLOR] 11:35 0:10 [kworker/u:4] root 93 0.3 0.0 0 0 ? S 11:35 0:21 [kworker/u:5] root 4743 0.0 0.0 0 0 ? S 13:06 0:00 [kworker/3:1] root 5759 4.5 0.0 0 0 ? S 12:38 1:52 [kworker/0:3] root 7327 7.3 0.0 0 0 ? S 13:08 0:51 [kworker/2:2] root 12484 0.0 0.0 0 0 ? S 13:12 0:00 [kworker/0:0] root 13891 0.0 0.0 0 0 ? S 13:14 0:00 [kworker/2:1] root 15858 0.0 0.0 0 0 ? S 11:48 0:02 [kworker/3:2] root 16894 0.0 0.0 0 0 ? S 12:48 0:00 [kworker/3:3] root 16926 0.0 0.0 0 0 ? S 12:23 0:01 [kworker/1:1] root 18354 0.0 0.0 0 0 ? S 13:18 0:00 [kworker/0:2]

what should I do ?
I have SLE support… May I open a Bug Report ? how ?
Please help

Regards,
Muhammad Sharfuddin[/QUOTE]