Gitlab on a minimal requirement Server

2G won't cut it. Gitlab is a notorious memory hog.

From the docs: https://docs.gitlab.com/ee/install/requirements.html

4GB RAM is the required minimum memory size

Official doc states flat out "Gitlab has memory leaks" (https://docs.gitlab.com/ee/administration/operations/unicorn.html#unicorn-worker-killer)

More details:

https://about.gitlab.com/handbook/engineering/development/enablement/memory/

https://news.ycombinator.com/item?id=17379523