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Spencer Owen

The art of progress is to preserve order amid change and preserve change amid order - Alfred North Whitehead

why is gitlab-ci running slowly?

I use gitlab and gitlab-ci and love it. It is the best self hosted CI / Version control system out there in my opinion.

I noticed a strange behavior where running knife upload from my workstation would return within seconds, where as the same command as a gitlab-ci job would take over 2 minutes.

Grr, 6 minutes for a build? Thats way too long.

If you have seen the same problem, jump to the bottom for the tl;dr version.

Through trial and error, I found that there are two work arounds:

# Takes 2+ minutes
sudo -i -u gitlab-runner knife upload --chef-repo-path . roles -V -n
# Takes seconds to run
sudo -u gitlab-runner knife upload --chef-repo-path . roles -V -n
# Takes seconds to run
sudo -i -u gitlab-runner /usr/bin/knife upload --chef-repo-path . roles -V -n

This is progress. It looks like using sudo with -i (simulate initial login) is causing problems. Also giving the full path fixes the issue. Thats when I stumbled on this SO question:

Through more trial and error, it definitely looks to be a ruby problem. My gitlab build runner is ubuntu 14.04 using the default ruby 1.9 from apt (no RVM or rbenv). Sure enough, ruby commands take a long time

# Returns in milliseconds
time /usr/bin/env which
# Returns in minutes
time /user/bin/env ruby

Hmmm… Sounds like a problem with the path.

Looking at the shadow file shows some interesting information:

getent shadow gitlab-runner

Looking at the first character after gitlab-runner, we see !. That indicates that the user account has logins disabled. That gets me thinking, the user probably has a different PATH.

# My user path
env | grep PATH
# gitlab-runner path
sudo -i -u gitlab-runner env | grep PATH

No wonder. The gitlab-runner has a super weird path to a non existent RVM installation. I’m guessing that there is a 1 minute timeout looking at the first 2 weird paths, then when it gets to /usr/local it returns immediately.

Success, I decided to fix the problem with the work around of adding /usr/bin/ to the knife command, instead of fixing ruby on the vm, since it will be replaced with docker containers and gitlab multi runner soon.

Success. 25 seconds for a build is more like it

tl;dr make sure you use the full path to knife in your gitlab-ci (/usr/bin/knife)

  stage: deploy
    - /usr/bin/knife upload --chef-repo-path . environments