I run a small self-hosted observability tool on the cheapest VPS I could find on purpose: 2 cores, 2 GB RAM, 20 GB SATA SSD. It ingests errors, traces and metrics from two low-traffic sites of mine. The stack is three containers — a Go app, PostgreSQL, and ClickHouse.

One evening docker stats showed ClickHouse sitting on 880 MB of its 1 GB limit...