In order to run GitLab w/o any tweaks you need 1GB Linode.
You can start it on 512 but you need to setup unicorn to use only 1 worker and you need at least 200MB of swap
Maybe someone who has the knowledge can write tutorial about configuring GL to run on average VPS?
And, as I have the chance, I want to thank you and whole GitLab team for a really great work! I'm using GL localy and I'm very pleased with it.