From time to time, often after I've restored from sleep or finished playing a Steam game, one of my CPU cores is pinned at 100% with no indication of what might be doing it. Running htop, btop, or GNOME system monitor all show the same thing: CPU0 at 100% while the rest are doing near-nothing, and no process in particular seems to be using those resources.
If I restart, it's back to normal, and sometimes I can play a game in Steam or let the computer go to sleep and it doesn't do this, but it happens often enough that's annoying/confusing so I'd like to know if there's a way to either (a) diagnose which processes are using which CPU cores, or (b) somehow "reset" the checking of these values to make sure that something's not just being misreported.
This is a desktop system running Arch & GNOME.
Show kernel threads, it's a setting in the htop config menu that is off by default.
There it is! Thank you! It's a process owned by root called
kworker/0:0+kacpid. Any idea what that is?[Edit 1] Interestingly, I can't even
kill -9it.[Edit 2] With
kworker kacpidto work with, I did a quick search and found this SO page that has some interesting information that I only partially understand, but the following worked like a charm:It's not clear to me what an interrupt is or whether this
gpe09value is meant to be persistent across reboots, or why this only seems to be happening in the last couple months, but if I can make it go away by running the above from time to time, I guess it's alright?That's a kernel worker for ACPI. It sounds like you may have a driver for something that is misbehaving.
More likely is the device firmware and you likely can't fix that.