http://dacxzjk3kq5mmepbdd3ai2ifynlzxsnpl2cnkfhridqfywihrfftapid.onion/help/administration/monitoring/prometheus/gitlab_metrics.md
For self-compiled installations, you must configure it yourself.
Collecting the metrics
GitLab monitors its own internal service metrics, and makes them available at the
/-/metrics endpoint. Unlike other Prometheus exporters, to access
the metrics, the client IP address must be explicitly allowed .