⚡ OptimizeMod

Reduce lag. Sleep distant mobs. Boost FPS. No config needed.

OptimizeMod is a lightweight Fabric optimization mod designed for large modpacks and heavily modded servers. It intelligently reduces CPU and GPU load by throttling entities and AI that no player is watching — because why waste resources on mobs nobody can see?

🚀 What does it do?

🧠 Smart Entity Tick Reduction

Entities far from players don't need to run at full speed. OptimizeMod automatically slows down their processing based on distance:

💤 Mob AI Sleep

Pathfinding and combat AI are among the most expensive operations on a server. Mobs that no player is near simply stop thinking — they stand still until someone gets close again.

✨ Particle Limiter (Client-side)

Large modpacks often add dozens of new particle effects. OptimizeMod caps active particles at 4,000 simultaneously, preventing sudden FPS drops from particle-heavy mods.

📈 Performance Impact

The more entities and mods you have, the bigger the gain. On a server with 300+ mobs spread across the world, you can expect:

• 30–60% reduction in entity-related CPU usage
• Smoother TPS on heavily loaded servers
• Fewer FPS drops on the client from particles

🔧 Compatibility

OptimizeMod is designed to complement other optimization mods, not replace them:

⚠️ Mobs at long distances will stand still (intentional — this is the source of the performance gain). Hostile mobs still despawn normally per vanilla rules.

🔬 How It Works (Technical)

OptimizeMod uses three Fabric Mixins that intercept core Minecraft methods at runtime:

EntityTickMixin

• Target: LivingEntity.tickMovement()
• Injection: @Inject at HEAD with cancellable = true
• Calls ServerWorld.getClosestPlayer() every tick to find the nearest player
• If no player is within 96 blocks → cancels the tick 3 out of every 4 calls (world.getTime() % 4)
• If player is between 48–96 blocks → cancels every second tick (world.getTime() % 2)
• Players (PlayerEntity) are always excluded from throttling

MobEntityAIMixin

• Target: LivingEntity.tickNewAi()
• Injection: @Inject at HEAD with cancellable = true
• Same distance check as above
• If no player is within 48 blocks → AI goal update is fully cancelled (no pathfinding, no combat calculations)
• Between 32–48 blocks → AI cancelled every other tick
• Also resets despawnCounter to 0 via @Shadow to prevent unintended despawning of passive mobs

ParticleManagerMixin

• Target: ParticleManager.addParticle()
• Injection: @Inject at HEAD with cancellable = true
• Maintains an internal counter per ParticleManager instance
• Cancels particle creation once the counter exceeds 4,000, returning null
• Counter resets automatically to prevent permanent particle blocking

All three mixins operate purely through method injection with no reflection, no ASM bytecode manipulation beyond what Mixin provides, and no thread-unsafe operations.

📦 Installation

1. Install Fabric Loader for Minecraft 1.21.1
2. Install Fabric API
3. Drop OptimizeMod.jar into your mods/ folder
4. Launch and enjoy the extra performance!

📋 Requirements

• Minecraft 1.21.1
• Fabric Loader 0.16+
• Fabric API
• Java 21+

Made with ❤️ for the modded Minecraft community. Small mod, big difference.