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 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

• Profile first: Identify actual bottleneck (CPU/GPU/Memory)

• Measure baseline: Record before optimization

• Optimize bottleneck: Focus on biggest impact

• Measure improvement: Validate changes

• 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)

Reference Documentation

Profiling and Optimization Patterns

Detailed profiling workflows:

• Unity Profiler module usage

• Draw call reduction techniques

• GPU instancing and SRP Batcher patterns

Related Skills

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

Best Practices

• Profile on target platform: Editor performance differs

• Optimize systematically: Measure, optimize, validate

• Quality settings: Provide options for different hardware

• Balance visuals vs performance: Adjust based on target

• Test on low-end: Ensure minimum spec performance