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I recently installed Ubuntu 12.04 on my Samsung laptop alongside Windows 7. Whenever I use Ubuntu (even when its idle) kworker uses almost 90% of one of 8-cores. Even though it doesn't really affect my usage, it bugs me and I am afraid of that it might harm my processor. I even tried installing another Linux distro (Linux Mint), and kworker caused the same problem. So I don't know what to do. I would really appreciate your help.

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3 Answers 3

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Instead I think this CPU usage is not normal and is related to the well-known kworker bug: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/887793

The solution for me and for many others was, first of all, find out the "gpe" that is causing the bad stuff with something like:

grep . -r /sys/firmware/acpi/interrupts/

and check for an high value (mine was gpe13 - with a value like 200K - so, you have to change it accordingly, if differs). After that:

~ cp /sys/firmware/acpi/interrupts/gpe13 /pathtobackup
~ crontab -e

Add this line, so it will be executed every startup/reboot:

@reboot echo "disable" > /sys/firmware/acpi/interrupts/gpe13

Save/exit. Then, to make it work also after wakeup from suspend:

~ touch /etc/pm/sleep.d/30_disable_gpe13
~ chmod +x /etc/pm/sleep.d/30_disable_gpe13
~ vim /etc/pm/sleep.d/30_disable_gpe13

Add this stuff:

#!/bin/bash
case "$1" in
    thaw|resume)
        echo disable > /sys/firmware/acpi/interrupts/gpe13 2>/dev/null
        ;;
    *)
        ;;
esac
exit $?

Save/exit, done.

Tested and working on :

Ubuntu 12.10 on Samsung Chronos 7 series - Model no. NP700Z7C --
Ubuntu 16.04.2 on Clevo - Model no. P650RS --
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  • 2
    Perfect! This really works on my laptop with Ubuntu 12.04 LTS!
    – Kevin Dong
    Apr 13, 2014 at 5:41
  • 3
    instead of setting the file /etc/pm/sleep.d/30_disable_gpe13 i've edited the file /etc/rc.local and added "echo disable > /sys/firmware/acpi/interrupts/gpe13 2>/dev/null" (before the exit 0) and now it's working, thanks
    – Joaolvcm
    May 22, 2014 at 14:41
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    14.10 still has this problem (MacbookPro Retina, late 2013). Found gpe06:94815545 and gpe17:10621, and after disabling the gpe06, kworker no longer appears at the top of the CPU ussage list, and then I could event see the power indicator increasing the remaining time left on battery power. Mar 7, 2015 at 23:28
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    Thank you so much for this! I was having this issue.. Every time I opened a torrent app the CPU usage went from 0 to 100% all the time.. My first thought was that was a NTFS problem.. but no. KTORRENT was at 90% and used your guide... all works fine now :-)
    – Mariano L
    Apr 9, 2016 at 23:42
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    This answer is a lifesaver. It's a shame to see that a serious 9 year old bug is still around, and apparently even affects the latest versions of Ubuntu.
    – Gabriel
    Oct 13, 2018 at 21:10
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The CPU usage seems to be normal, there's only 1 CPU (CPU1) that has high usage. In all there are total 3 process that are in the running state two of them being kworker and gnome-system-mo (the first 2 processes in the top command screen short you added).

"kworker" is a placeholder process for kernel worker threads, which perform most of the actual processing for the kernel, especially in cases where there are interrupts, timers, I/O, etc. These typically correspond to the vast majority of any allocated "system" time to running processes. It is not something that can be safely removed from the system in any way, and is completely unrelated to nepomuk or KDE (except in that these programs may make system calls, which may require the kernel to do something)

For more information about kworker please have look at the following link:- What's KWorker and it's importance

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  • Thank you for your quick answer! I have another question then. Is there way to make the processor use other CPUs instead of using only one core for its most of processes.
    – Yusuf
    Aug 16, 2012 at 13:32
  • I solved the problem by installing phc-intel packages from link.
    – Yusuf
    Aug 16, 2012 at 13:46
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    Not at all normal that a core is continuing to run at 80% when the system is idle.
    – vanadium
    Feb 21, 2020 at 10:25
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I installed Linux Mint 17 yesterday and noticed this evening that kworker was consuming 100% of one of 4 cpus. I ran the above check, but did not find anything other than 0 for the interrupts.

While examining the services that I normally have running, I noticed that shutting down the nfs server dropped the kworker thread back to zilch. A restart of the nfs server did not fix the issue.

I found this bug report (https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1322407), which indicates that a similar nfs server problem was fixed in kernel 3.13.0-32.57. The latest update on Mint 17 appears to be running kernel 3.13.0-24-generic, so I don't have the fix in the kernel that I am running. I don't know if this will help anyone else but I systematically went to each nfs client machine and did a 'umount -a -t nfs' and waited to see if it had any effect. I found the client that seemed to have been causing the issue as the kworker dropped to nothing after I unmounted. I remounted the nfs shares on the client 'mount -a -t nfs' and the problem did not return.

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