Unity Performance Optimization

Overview

Performance optimization for Unity games focusing on profiling and systematic optimization.

Foundation Required: unity-csharp-fundamentals (TryGetComponent, FindAnyObjectByType, null-safe coding)

Core Topics:

• •Unity Profiler analysis
• •Draw call reduction
• •GPU instancing and SRP Batcher
• •LOD (Level of Detail)
• •Occlusion culling
• •Object pooling
• •Memory optimization

Quick Start

Collection & Object Pooling

GC-free pooling is critical for performance. Use Unity's built-in UnityEngine.Pool namespace (2021.1+):

using UnityEngine.Pool;

// Temporary collection pooling - eliminates GC spikes
List<Enemy> enemies;
using (ListPool<Enemy>.Get(out enemies))
{
    GetComponentsInChildren(enemies);
    ProcessEnemies(enemies);
} // Auto-released

See unity-collection-pool skill for comprehensive patterns:

• •ListPool, HashSetPool, DictionaryPool for temporary collections
• •ObjectPool<T> for component/prefab pooling
• •Advanced patterns: Keyed pools, auto-return, ECS integration

Performance Targets

• •Mobile: 30-60 FPS, <100 draw calls
• •Desktop: 60+ FPS, <500 draw calls
• •VR: 90 FPS minimum, <200 draw calls

Profiling Workflow

1. •Profile first: Identify actual bottleneck (CPU/GPU/Memory)
2. •Measure baseline: Record before optimization
3. •Optimize bottleneck: Focus on biggest impact
4. •Measure improvement: Validate changes
5. •Repeat: Until target performance reached

Optimization Checklist

CPU Optimization

• •✅ Reduce Update/FixedUpdate calls
• •✅ Object pooling for frequently spawned objects
• •✅ Cache component references in Awake/Start
• •✅ Use events instead of polling

GPU Optimization

• •✅ Static batching for static objects
• •✅ GPU instancing for identical meshes
• •✅ Reduce SetPass calls via material sharing
• •✅ LOD groups for distant objects
• •✅ Occlusion culling for large scenes

Memory Optimization

• •✅ Texture compression
• •✅ Mesh optimization (reduce vertex count)
• •✅ Audio compression and streaming
• •✅ Asset bundle management
• •✅ Unload unused assets
• •✅ Collection pooling (see unity-collection-pool skill)

Related Skills

• •unity-collection-pool: GC-free collection management with ListPool, HashSetPool, DictionaryPool, and ObjectPool. Essential for eliminating GC spikes.

Best Practices

1. •Profile on target platform: Editor performance differs
2. •Optimize systematically: Measure, optimize, validate
3. •Quality settings: Provide options for different hardware
4. •Balance visuals vs performance: Adjust based on target
5. •Test on low-end: Ensure minimum spec performance