Upgrade Runners to 9.0.1 plan

Because of upcoming release we should plan an upgrade process for our runner managers:

  • rc.3 release:
    • upgrade gitlab-runner-builder.gitlap.com to v9.0.0-rc.3 (when GitLab.com will be running RC6)
    • upgrade docker-ci-X.gitlap.com to v9.0.0-rc.3 (when GitLab.com will be running RC6)
  • stable release:
    • upgrade gitlab-runner-builder.gitlap.com to v9.0.0 (at 2017-03-22)
    • upgrade gitlab-runner-builder.gitlap.com to v9.0.1 (at 2017-04-05)
    • upgrade docker-ci-X.gitlap.com to v9.0.1 (at 2017-04-05)
    • upgrade gitlab-shared-runners-manager-(1|2).gitlab.com to v9.0.1 (at 2017-04-05)
    • upgrade shared-runners-manager-(1|2).gitlab.com to v9.0.1 (at 2017-04-05)
    • upgrade shared-runners-manager-(3|4).gitlab.com_ to v9.0.1 (at 2017-04-05)

Runner v9.0 will contain some breaking changes. The most important one is that Runner 9.0 will be using a new v4 API version of GitLab (which is working properly with new Runner starting with GitLab CE/EE v9.0.0-rc6).

With gitlab-org/gitlab-ci-multi-runner!518 we've added a configuration setting to limit concurrency in requesting jobs from GitLab by one Runner. As proposed by @ayufan (https://gitlab.com/gitlab-org/gitlab-ci-multi-runner/merge_requests/518#note_25790592) for updated runner managers we should set request_concurrency to 3 or 4 for each runner. This should be added in runners -> [name] -> global scope, so in role description it would look like:

(...)
"runners": {                                                                                                                                                                                                
  "docker_auto_scale": {                                                                                                                                                                                    
    "global": {                                                                                                                                                                                             
      "name": "docker-auto-scale",
      "limit": 400,
      "request_concurrency": 3,
      "url": "https://gitlab.com/ci",
      "token": null,
      "executor": "docker+machine"
    },
    "docker": {
(...)