Gitlab minimal memory installation via docker.

docker-compose.yml

web:
  image: 'gitlab/gitlab-ee:latest'
  restart: always
  hostname: 'gitlab.example.com'
  environment:
    GITLAB_OMNIBUS_CONFIG: |
      external_url 'https://gitlab.example.com'
      # Add any other gitlab.rb configuration here, each on its own line
      puma['worker_processes'] = 0
      sidekiq['max_concurrency'] = 10
      prometheus_monitoring['enable'] = false
      gitlab_rails['env'] = {'MALLOC_CONF' => 'dirty_decay_ms:1000, muzzy_decay_ms:1000'}
      gitaly['cgroups_count'] = 2
      gitaly['cgroups_mountpoint'] = '/sys/fs/cgroup'
      gitaly['cgroups_hierarchy_root'] = 'gitaly'
      gitaly['cgroups_memory_enabled'] = true
      gitaly['cgroups_memory_limit'] = 250000
      gitaly['cgroups_cpu_enabled'] = true
      gitaly['cgroups_cpu_shares'] = 512
      gitaly['concurrency'] = [{'rpc' => "/gitaly.SmartHTTPService/PostReceivePack", 'max_per_repo' => 3}, {'rpc' => "/gitaly.SSHService/SSHUploadPack", 'max_per_repo' => 3}]
      gitaly['env'] = {'LD_PRELOAD' => '/opt/gitlab/embedded/lib/libjemalloc.so', 'MALLOC_CONF' => 'dirty_decay_ms:1000,muzzy_decay_ms:1000', 'GITALY_COMMAND_SPAWN_MAX_PARALLEL' => '2'}
  ports:
    - '80:80'
    - '443:443'
  volumes:
    - '/var/lib/gitlab/config:/etc/gitlab'
    - '/var/lib/gitlab/logs:/var/log/gitlab'
    - '/var/lib/gitlab/data:/var/opt/gitlab'