Prometheus Exporter

Prometheus Exporter

A PaperMC plugin that exposes server metrics to Prometheus via an HTTP endpoint.

The metrics endpoint starts automatically on port `9940`.

Configuration

`plugins/PrometheusExporter/config.yml`:

```yaml metrics-port: 9940 collection-interval-ticks: 20 # 20 ticks = 1 second ```

Scraping

Point Prometheus at:

``` http://<server-ip>:9940/metrics ```

Example `prometheus.yml`:

```yaml scrape_configs: - job_name: minecraft static_configs: - targets: ["<server-ip>:9940"] ```

Metrics

Server

| Metric | Labels | Description | | --------------------------- | ------------------------------ | --------------------------------------------------- | | `mc_tps` | `window` (`1m`, `5m`, `15m`) | Server ticks per second | | `mc_mspt_milliseconds` | — | Average milliseconds per tick (last 100 ticks) | | `mc_tick_time_milliseconds` | `quantile` (`max`, `p95`) | Tick duration quantiles over the last 100 ticks | | `mc_players_online` | — | Current online player count | | `mc_players_max` | — | Maximum player slots | | `mc_current_tick` | — | Monotonically increasing tick counter | | `mc_worlds` | — | Number of currently loaded worlds |

Per-world

| Metric | Labels | Description | | -------------------------------- | --------------- | -------------------------------------------------------- | | `mc_world_players` | `world` | Players per world | | `mc_world_loaded_chunks` | `world` | Loaded chunks per world | | `mc_world_entities` | `world` | Total entity count per world | | `mc_world_entities_by_type` | `world`, `type` | Entity count broken down by type (e.g. `zombie`, `cow`) per world | | `mc_world_tile_entities` | `world` | Tile entity count per world | | `mc_world_ticking_tile_entities` | `world` | Ticking tile entity count per world | | `mc_world_time` | `world` | In-game clock (0–24000); tracks day/night cycle | | `mc_world_storm` | `world` | 1 if a storm is active, 0 otherwise | | `mc_world_thundering` | `world` | 1 if a thunderstorm is active, 0 otherwise |

Per-player

| Metric | Labels | Description | | ----------------------------- | ---------------- | ---------------------------------------------- | | `mc_player_ping_milliseconds` | `player` | Latency per player | | `mc_player_health` | `player` | Current health per player | | `mc_player_max_health` | `player` | Max health per player (useful when custom attributes are applied) | | `mc_player_food_level` | `player` | Hunger level per player (0–20) | | `mc_player_saturation` | `player` | Saturation per player (0.0–20.0+) | | `mc_player_xp_level` | `player` | XP level per player | | `mc_player_xp_progress` | `player` | Fractional XP progress within current level (0.0–1.0) | | `mc_player_total_experience` | `player` | Total accumulated XP per player | | `mc_player_flying` | `player` | 1 if the player is flying, 0 otherwise | | `mc_player_gamemode` | `player` | Numeric active gamemode (0 = survival, 1 = creative, 2 = adventure, 3 = spectator) |

JVM

| Metric | Labels | Description | | ------- | ------- | ------------------------------------- | | `jvm_*` | various | JVM heap, GC, threads, classloaders |