Add earlyoom to dev desktop

[Noratrieb]

Sometimes the dev desktop just OOMs and dies because someone committed a happy little accident, as one does. Luckily Linux has an OOM killer, sadly it's pretty useless in practice.

Luckily there's a userspace workaround! It works really well.

I don't know if we want any config for it. I set the freeSwapThreshold to 100 on my own computer to never swap before killing, I don't know if that would matter for the dev desktop. I think it makes sense to keep it at the default for now unless that causes problems.

[Noratrieb]

@pietroalbini was complaining to me about the dev desktop dying sometimes and told me i should do this uwu hi

[marcoieni]

Hey Nora, thank you for contributing!
I tested it on our staging dev desktops by running ./x check and earlyoom killed the process almost immediately (the staging desktop only has 1GB of memory 😅).

So this looks good to me. Let's try it with default settings as you said and let's see how it goes. If people complain that their processes get killed too often we can re-evaluate this :)

Just one thing. Instead of adding a task like you did, I think it's cleaner if you add earlyoom to this list:

simpleinfra/ansible/roles/dev-desktop/tasks/dependencies.yml

Line 11 in 5bbba89

- name: Install packages

What do you think?

For anyone else. This is the gist of what earlyoom does (from their readme):

earlyoom checks the amount of available memory and free swap up to 10 times a second (less often if there is a lot of free memory). By default if both are below 10%, it will kill the largest process (highest oom_score).

[marcoieni]

I installed earlyoom in all dev-desktops. You can verify this by running systemctl status earlyoom.
Thanks for your contribution Nora! 😁