Disable core dumps
A coredump is something the kernel initiates when an application crashes/segfaults. Nowadays it usually passes that task on to systemd. This takes time, storage and CPU.
I'm not a system developer. I have no idea what to do with a coredump. I don't need it.
There's also some threads online suggesting this could help against shutdown lags.
I won't write much here, because there's a very good and simple cybercity article out there that does it better than I ever could.
In case the site should ever go down , it is archived here.