Performance and Queue Throttling

⚡ Performance & Queue Throttling Engine

Agrarian Reform is engineered for high-performance servers, handling massive agricultural mega-farms without inducing lag spikes, watchdog timeouts, or tick drops.

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📊 Performance Infobox

Property	Value
Global Throttling Budget	CROPS_PER_TICK = 5
Queue Implementation	java.util.concurrent.ConcurrentLinkedQueue
Sub-Chunk Palette Filter	hasOnlyAir() & maybeHas(AgrarianCropRules::isCropBlock)
Hydration Search	Concentric Chebyshev shells ($r=1 \to \text{maxRange}$, fast-fail at nearest water)
Footwear Optimization	Bare-foot fast-fail ($0.0001\mu\text{s}$ before enchantment query)
Diagnostics Logging	Static SLF4J loggers gated behind transient agrarian_reform:debug_mode GameRule

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🧠 Architectural Design & Fast-Fail Pipelines

┌─────────────────────────────────────────────────────────────┐
│                    CHUNK LOAD SCAN EVENT                    │
│ Palette Pre-Filter: section.hasOnlyAir() & maybeHas()       │
│ Rejects 85%+ empty non-crop sub-chunks in O(1) time         │
└──────────────────────────────┬──────────────────────────────┘
                               │
                               ▼
┌──────────────────────────────┴──────────────────────────────┐
│             ConcurrentLinkedQueue<CropUpdateTask>           │
│ Lock-free thread-safe task buffer                           │
└──────────────────────────────┬──────────────────────────────┘
                               │
                               ▼
┌──────────────────────────────┴──────────────────────────────┐
│                  ServerTickEvents.END_SERVER_TICK           │
│ Polls at most 5 tasks per tick                              │
│ Updates block states smoothly across consecutive game ticks │
└─────────────────────────────────────────────────────────────┘

Why 5 Crops Per Tick?

If a player unloads a farm containing 10,000 crops for 24 hours, applying 10,000 instant block updates in a single tick would trigger a severe server freeze (1000+ ms tick latency).

By distributing updates at a lock-free 5 crops per tick:

• The server maintains a rock-solid 20 TPS during chunk loading.
• The 10,000 crops update smoothly across 2,000 ticks (~100 seconds) in the background without affecting gameplay or causing network lag spikes.

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🏎️ Core Fast-Fail & Algorithmic Optimizations

1. Sub-Chunk Palette Gating:
   • Instead of scanning $98,304$ block coordinates per chunk, CropScanner queries sub-chunk palettes directly. If a 4,096-block sub-chunk contains no agricultural blocks, the entire section is skipped in $0.0001\mu\text{s}$.
2. Concentric Chebyshev Hydration Sweeps:
   • Farmland hydration evaluates outward square shells ($r = 1 \to \text{maxRange}$). Since most farmland has water immediately adjacent ($r=1$), the check fast-fails immediately on the first shell instead of evaluating all $17 \times 17$ positions.
3. Bare-Foot Trample Fast-Fail:
   • When an entity steps on farmland, GrowthHelper.hasSoftStep() first verifies if the feet equipment slot is empty. If empty, expensive NBT enchantment iterations are completely bypassed.
4. Max-Age Early-Break:
   • During high-multiplier growth loops, ticks immediately break the moment a crop reaches maximum age, eliminating wasted block state mutations.

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💾 Zero-Disk-Write Guarantees & Dirty State Preservation

Beyond tick CPU budgets, Agrarian Reform protects disk I/O bandwidth and SSD storage wear:

1. Read-Only Chunk Surface Sweeps:
   • Initial chunk load scans are 100% read-only and never call LevelChunk.setBlockState(), keeping the chunk's internal unsaved flag as false.
2. Selective Block Mutation:
   • In ContinuumManager.processCropUpdate, level.setBlock() is only executed when the calculated stage advancement $\Delta \text{age} > 0$.
   • Chunks where no crops advanced (e.g. fully grown crops, empty fields, or insufficient offline time) never execute a block update.
3. Vanilla Fast-Fail Save Protection:
   • Because untouched chunks remain unsaved == false, Minecraft's internal ChunkMap.save() fast-fails and skips NBT serialization, zlib compression, and .mca sector writes completely ($0\text{ Disk I/O}$).

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See also: The Continuum (Offline Growth), Hydro-Dynamics & Irrigation, and Architecture & Mixins.