### Problem to solve We're trying to track for inactive groups (which can point to per-group resources that can be potentially be shut down or hibernated for cost savings) and currently have to iterate through the group projects and check the `last_activity_at` of every project. However we're seeing this date isn't always accurate. In addition to the [15 minute delay](https://gitlab.com/gitlab-org/gitlab-ce/issues/42815) due to caching (for UI performance), we're seeing some projects not updated more than a hour after the last push. ### Proposal Add `last_activity_at` and `last_activity_project` field to groups, accessible via API, and whenever a project has its `last_activity_at` updated, also update the group with matching date and ID of the project. ### What does success look like, and how can we measure that? The response to an HTTP GET to `<server>/api/v4/groups/<id>` includes the last project with Git activity and the date+time of that activity. ### Links / references