Ubuntu – Why does kworker cpu usage get so high?


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

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Best Answer

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:

case "$1" in
        echo disable > /sys/firmware/acpi/interrupts/gpe13 2>/dev/null
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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