Get rid of the large authorized keys (SSH) file
Based on Jacob's comment on gitlab-git-http-server#2 (closed)
FYI AuthorizedKeysCommand is an offical part of OpenSSH 6.2 and newer, it is no longer a 'patch'.
AuthorizedKeysCommand allows you to run a command that spits out the full authorized_keys file. So for us it would be something like
curl localhost:8080/api/internal/authorized_keys, and the response body would be 50-100 MB or so. That means every time some client connects over SSH, SSHD has to start a subprocess, read 50-100MB from its standard output, and find the key of the client in there. I am not sure if that is going to scale well.
Who knows, it is an interesting problem.