<!--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=213145) </details> <!--IssueSummary end--> We've encountered before the performance degradations due to fetching all commits for a merge request: https://gitlab.com/gitlab-org/gitlab/-/issues/35542. The `limit` param has been introduced for narrowing the number of commits fetched: https://gitlab.com/gitlab-org/gitlab/-/blob/master/app/models/merge_request.rb#L423. The `limit` is optional, but we need to make sure that we avoid calling this method without it. However, we need to fix all the cases that are using this method without a `limit` before we can make it required