Is there a daemon that will kill any processes using above a specified % of CPU? I’m having issues where a system is sometimes grinding to a halt due to high CPU usage. I’m not sure what process is doing it (can’t htop as system is frozen); ideally I’d like a daemon that automatically kills processes using more than a given % of CPU, and then logs what process it was for me to look back on later. Alternatively something that just logs processes that use a given % of CPU so that I may look back on it after restarting the system.

The system is being used as a server so it’s unattended a lot of the time; it’s not a situation where I did something on the computer and then CPU usage went up.

Edit: Thanks to the comments pointing out it might be a memory leak instead of CPU usage that’s the issue. I’ve set up earlyoom which seems to have diagnosed the problem as a clamd memory leak. I’ve been running clamd on the server for ages without problems so might be the result of an update; I’ve disabled it for now, and will keep monitoring the situation to see if earlyoom catches anything else, or if the problem keeps occurring I’ll try some of the other tools people have suggested.

  • nyan@sh.itjust.works
    4·
    9 hours ago

    If you dare, you can try temporarily killing the system’s swap (using the swapoff command) and see what happens. With no swap, the standard OOM reaper should trigger within a couple of minutes at most if it’s needed, and it should write an entry to the system log indicating which process it killed.

    Note that the process killed is not necessarily the one causing the problem. I haven’t had the OOM trigger on me in many years (I normally run without swap), but the last time it did, it killed my main browser instance (which was holding a large but not increasing amount of memory at the time) rather than the gcc instance that was causing the memory pressure.