Search code examples
linuxkuberneteslinux-kernelsystemdcoredump

Modify core dump disk space utilization per node


As per the official man page documentation for coredump.conf, the core dump disk space utilization per node in Kubernetes can be modified by changing the MaxUse section to X%, and by default, it is 10%.

https://man7.org/linux/man-pages/man5/coredump.conf.5.html

I have done the following things :

  • 1st Solution which I tried: Modified /etc/systemd/coredump.conf by removing # before MaxUse and changes it to 20%

    cat /etc/systemd/coredump.conf
    MaxUse=20%
    

    After that, I ran "sudo systemctl daemon-reload" in order to reflect the change but it didn't work.

  • 2nd Solution which I tried : Adding /etc/systemd/coredump.conf.d/custom.conf to override /etc/systemd/coredump.conf. This option was specified here: https://wiki.archlinux.org/index.php/Core_dump

    [Coredump]
    MaxUse=20%
    

    After that, I ran "sudo systemctl daemon-reload" in order to reflect the change but it didn't work. I did multiple cores just to check whether both solutions are working but it didn't work:

    I have core my test application and just to get large cores I have used the below-mentioned command:

    $ sudo dd if=/dev/zero of=abc.xz bs=1024 count=10240000
    

    While testing this my core dump directory /var/lib/systemd/coredump/ had over 150G of core.


Solution

  • Looks like the docs are misleading and say that it defaults to MaxUse to be 10%. But it seems like the systemd code shows that it's parsed in terms of Bytes, Kbytes, Mbytes, etc. You can try something like:

    [Coredump]
    MaxUse=20G