https://docs.gitlab.com/omnibus/settings/memory_constrained_envs.html

https://docs.gitlab.com/omnibus/settings/memory_constrained_envs.html#disable-additional-in-application-monitoring


other sources:
https://edspencer.me.uk/posts/2017-07-30-reducing-the-amount-of-memory-used-by-gitlab/
https://theorangeone.net/posts/lightweight-gitlab/