<!--IssueSummary start--> <details> <summary> Everyone can contribute. [Help move this issue forward](https://handbook.gitlab.com/handbook/marketing/developer-relations/contributor-success/community-contributors-workflows/#contributor-links) while earning points, leveling up and collecting rewards. </summary> - [Close this issue](https://contributors.gitlab.com/manage-issue?action=close&projectId=278964&issueIid=199199) </details> <!--IssueSummary end--> ## Problem We shipped [Merge Train](https://docs.gitlab.com/ee/ci/merge_request_pipelines/pipelines_for_merged_results/merge_trains/) a few release back. This is a powerful tool to validate MRs to be merged in a proper order. We have a customer trying to evaluate merge train effectiveness and make operational decisions about continued adoption, but they lack visibility into train performance metrics and failure patterns. We should show additional metrics that can demonstrate the impact of the merge train ## Customer Needs - Monitor merge train reset/cancellation frequency - Daily Average Merge Train Queue length - Measure the operational cost of train disruptions (especially from flaky tests) - Track efficiency metrics to determine if merge trains provide net value ## Proposed Metrics (To be Validated) - Show recent immediate merge performed without merge train (which potentially slows down trains) - Show the duration per merge. Average of merge time. Max/Min in a week. p95. etc. ## Reference - https://gitlab.com/gitlab-org/gitlab/issues/9186#note_154929645 - https://gitlab.com/gitlab-com/www-gitlab-com/issues/5177#note_275737200 - https://gitlab.slack.com/archives/CHLKE258E/p1580154874003400