Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.debian.kernel > #67658

Bug#966703: linux-image-4.19.0-10-amd64: kworker process with permanent high CPU load

Cross-posted to 2 groups.

Show key headers only | View raw

Control: tags -1 + moreinfo

Hi Dirk

On Sun, Aug 02, 2020 at 10:00:27AM +0200, Dirk Kostrewa wrote:
> Package: src:linux
> Version: 4.19.132-1
> Severity: normal
> 
> Dear Maintainer,
> 
> after booting the kernel 4.19.0-10-amd64, there is a kworker process running
> with a permanent high CPU load of almost 90% as reported by the "top"
> command:
> 
> $ top
> top - 09:48:19 up 0 min,  4 users,  load average: 1.91, 0.58, 0.20
> Tasks: 218 total,   2 running, 216 sleeping,   0 stopped,   0 zombie
> %Cpu(s):  0.8 us, 12.4 sy,  0.0 ni, 84.5 id,  0.0 wa,  0.0 hi,  2.3 si,  0.0
> st
> MiB Mem :  15889.4 total,  14173.1 free,    889.3 used,    827.0 buff/cache
> MiB Swap:      0.0 total,      0.0 free,      0.0 used.  14677.7 avail Mem
> 
>   PID USER      PR  NI    VIRT    RES    SHR S  %CPU  %MEM TIME+ COMMAND
>    64 root      20   0       0      0      0 R  86.7   0.0 0:47.41
> kworker/0:2+pm
>     9 root      20   0       0      0      0 S  20.0   0.0 0:08.84
> ksoftirqd/0
>   364 root     -51   0       0      0      0 S   6.7   0.0 0:00.50
> irq/126-nvidia
>  1177 dirk      20   0 2921696 122848  94268 S   6.7   0.8 0:02.23 kwin_x11
>     1 root      20   0  169652  10280   7740 S   0.0   0.1 0:01.56 systemd
>     2 root      20   0       0      0      0 S   0.0   0.0 0:00.00 kthreadd
> ...
> 
> The expected result after booting the kernel 4.19.0-10-amd64 is a kworker
> process with a CPU load close to 0%.
> 
> As a control, booting the previous kernel 4.19.0-9-amd64 does not show a
> high CPU load for the kworker process. Instead, the kworker CPU load
> reported by the "top" command is 0.0%.
> 
> Therefore, I suspect a bug in the kernel 4.19.0-10-amd64.
> 
> Neither "dmesg" nor "journalctl -b" show any messages containing "kworker".
> 
> I am using Debian/GNU Linux 10.5 with kernel 4.19.0-10-amd64 and libc6:amd64
> 2.28-10.
> 
> If you need more information, I would be happy to provide it.

To find out what could be the cause, could you have a look at
https://www.kernel.org/doc/html/latest/core-api/workqueue.html#debugging
this could help determining isolating why the kworker goes crazy.

Regards,
Salvatore

Back to linux.debian.kernel | Previous | Next — Next in thread | Find similar | Unroll thread

Thread

Bug#966703: linux-image-4.19.0-10-amd64: kworker process with permanent high CPU load Salvatore Bonaccorso <carnil@debian.org> - 2020-08-02 15:50 +0200
  Bug#966703: linux-image-4.19.0-10-amd64: kworker process with permanent high CPU load Salvatore Bonaccorso <carnil@debian.org> - 2020-08-02 18:30 +0200
    Bug#966703: linux-image-4.19.0-10-amd64: kworker process with permanent high CPU load Salvatore Bonaccorso <carnil@debian.org> - 2020-08-11 21:30 +0200
      Bug#966703: linux-image-4.19.0-10-amd64: kworker process with permanent high CPU load Dirk Kostrewa <dirk.kostrewa@mailbox.org> - 2020-08-12 13:10 +0200
        Bug#966703: linux-image-4.19.0-10-amd64: kworker process with permanent high CPU load Dirk Kostrewa <dirk.kostrewa@mailbox.org> - 2020-08-12 18:00 +0200
          Bug#966703: linux-image-4.19.0-10-amd64: kworker process with permanent high CPU load Salvatore Bonaccorso <carnil@debian.org> - 2020-08-12 18:10 +0200
            Bug#966703: linux-image-4.19.0-10-amd64: kworker process with permanent high CPU load Dirk Kostrewa <dirk.kostrewa@mailbox.org> - 2020-08-13 11:00 +0200
            Bug#966703: linux-image-4.19.0-10-amd64: kworker process with permanent high CPU load Dirk Kostrewa <dirk.kostrewa@mailbox.org> - 2020-08-21 11:40 +0200
          Bug#966703: linux-image-4.19.0-10-amd64: kworker process with permanent high CPU load Salvatore Bonaccorso <carnil@debian.org> - 2020-08-28 16:40 +0200
            Bug#966703: linux-image-4.19.0-10-amd64: kworker process with permanent high CPU load Salvatore Bonaccorso <carnil@debian.org> - 2020-08-29 11:40 +0200
              Bug#966703: linux-image-4.19.0-10-amd64: kworker process with permanent high CPU load Dirk Kostrewa <dirk.kostrewa@mailbox.org> - 2020-09-04 18:00 +0200
                Bug#966703: linux-image-4.19.0-10-amd64: kworker process with permanent high CPU load Salvatore Bonaccorso <carnil@debian.org> - 2020-09-04 19:20 +0200

csiph-web