ChunkGenerator

ChunkGenerator is a focused pre-generation plugin for Paper,
Purpur and Folia. It generates world chunks in a chosen shape around
any center point, adapts to your server's actual TPS in real time,
and keeps the BossBar honest about progress, speed and ETA — without
crashing the server when the chunk system saturates.

Why ChunkGenerator

• Adaptive, not reckless. A TPS-aware controller scales the
  inflight chunk pipeline up while your TPS holds and down the
  moment it slips. No fixed chunks-per-tick budget to misconfigure.
• Auto-tunes to your host. Start it with all defaults: the
  plugin reads availableProcessors() and maxMemory() at boot and
  picks a safe pipeline depth for your CPU and JVM heap. The
  resolved values are logged at startup along with the Paper tuning
  recommendation for your core count.
• OOM-safe. A memory-pressure circuit breaker scales the
  pipeline down past a configurable heap threshold and pauses new
  submissions entirely past the next, resuming automatically once
  the GC catches up. Specifically designed to survive container
  hosts (Pterodactyl, Docker) with aggressive MaxRAMPercentage.
• Survives restarts. Per-world progress is persisted atomically
  to YAML and resumed automatically when the server comes back up.

Features

• Pre-generation jobs over square, circle or rectangle
  zones with an optional explicit center (defaults to world spawn).
• One job per world; multiple worlds generate in parallel.
• Live BossBar for staff (chunkgenerator.bossbar), compact
  ActionBar for the player who launched the job, and a periodic
  console progress line with inflight/target, chunk/s,
  TPS, CPU and RAM readings.
• /cg status snapshots with progress percent, speed, ETA, server
  TPS, process CPU and JVM RAM usage.
• Pause / resume / cancel mid-flight with state preserved across
  restarts.
• Paper, Purpur and Folia all supported. Folia is
  handled through a reflection-based scheduler bridge so the plugin
  keeps a pure Paper-API compile classpath.
• LuckPerms integration with /op fallback when LuckPerms is
  absent.

Commands

| Command | What it does |
|---|---|
| /cg start <world> <shape> <size> [centerX centerZ] | Start a job (shape = square / circle / rectangle). |
| /cg stop <world> | Pause a running job (state preserved). |
| /cg resume <world> | Resume a paused job. |
| /cg cancel <world> | Cancel and discard a job's state. |
| /cg status [world] | Live snapshot of progress, perf and pipeline. |
| /cg list | List all known jobs. |
| /cg reload | Reload config.yml and messages.yml. |

Alias: /chunkgen.

Configuration

config.yml is split into a short Basics block
(target-tps, bossbar / actionbar / console toggles, auto-resume)
and an Advanced throttle section that most servers never need
to touch. All player-facing strings live in messages.yml with the
standard & color codes.

Maximising throughput

The plugin keeps Paper's chunk request queue saturated, but the real
ceiling is Paper's chunk worker count, not the plugin's queue
depth. Open config/paper-global.yml and raise:

chunk-system:
  worker-threads: <cores - 1>   # e.g. 5 on a 6-core host
  io-threads:     3

The default -1 is "auto", which usually allocates only around
cores / 2 workers — perfectly safe for a populated survival
server, but leaves most of the CPU idle during pre-generation. The
plugin prints the recommended values for your host in the startup
log.