Short answer: the Prefect Prometheus “exporter” doesn’t store any snapshot data. - In Prefect 3.x, the client metrics endpoint is just a Prometheus-compatible scrape target. It exposes current, in-process metrics; it does not persist history or keep “snapshots.” - Any retention of time series is handled by your Prometheus server (or remote storage), not by Prefect. Configure retention with your Prometheus flags (e.g.,

--storage.tsdb.retention.time=30d

) or its config. Helpful links: - Prefect client metrics settings (enable/port): Prefect 3 Settings reference - Prometheus retention/storage: Prometheus storage and retention Notes: - If the Prefect process restarts, those in-memory counters reset. Prometheus continues to have whatever historical data it scraped and stored per its retention. - If you were asking about Prefect’s event data (which some Prefect metrics derive from), that’s stored in the Prefect database and governed by event retention settings—not Prometheus. Can you confirm whether you meant the Prefect client metrics endpoint (Prometheus scrape target) or a different “prefect-prometheus exporter” package? If it’s the latter, please share a link or the exact package name/version so I can give specifics.