Performance Optimization

What it does

When your agent uses it

• The user mentions performance
• Low/dropping FPS
• Garbage collection/GC spikes
• The game runs slow

Example prompts

• “the game runs slow”
• “/performance-optimization”

Requirements

• Compatibility (from SKILL.md): Engine-agnostic methodology; profiler/tooling notes for Godot 4.x, Unity 6, and Unreal 5. Pairs with physics-tuning and the engine skills.

Workflow steps

5 steps, taken from the step headings in SKILL.md.

1. 1Frame budget math (turn "feels slow" into a number)
2. 2Measure with the engine profiler (do this before any fix)
3. 3Object pooling (stop allocating/freeing in hot loops)
4. 4Cut draw calls (the most common GPU-side win)
5. 5Kill per-frame allocations (GC spikes = stutter)

What it can do on your machine

Read from SKILL.md and the folder at commit fc215d4. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  No scripts in the folder and no shell commands in SKILL.md (its code samples are gdscript and csharp).

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  No URLs in SKILL.md.

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

• Compatibility

  Engine-agnostic methodology; profiler/tooling notes for Godot 4.x, Unity 6, and Unreal 5. Pairs with physics-tuning and the engine skills.

  From compatibility in the SKILL.md frontmatter.

Context cost

Performance Optimization loads about 2.3k tokens when it runs, and up to ~3.8k if it reads all its reference files. Until then it costs about 143 tokens; SKILL.md has 720 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~143

When it runs · the whole SKILL.md, loaded when a task matches

~2.3k

With references · SKILL.md plus every file in references/, read only if the agent opens them

~3.8k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from ukanwat/overtime at commit fc215d4, republished under its Apache-2.0 licence (© ukanwat). 720 words, ~2,300 tokens.

name

performance-optimization

description

Find and fix game performance problems methodically — measure with the engine profiler first, reason about the frame-time budget, locate the CPU-vs-GPU bottleneck, then apply the right fix: object pooling, draw-call batching, fewer allocations/GC spikes, and asset budgets. Engine- neutral method that pairs with each engine's profiler. Use when the user mentions performance, optimize, low/dropping FPS, frame drops, stutter, lag, profiler, frame budget, draw calls, batching, garbage collection/GC spikes, object pooling, or "the game runs slow".

compatibility

Engine-agnostic methodology; profiler/tooling notes for Godot 4.x, Unity 6, and Unreal 5. Pairs with physics-tuning and the engine skills.

license

Apache-2.0

metadata.engine

none

metadata.category

disciplines

metadata.difficulty

advanced

target FPS → frame budget:   60 FPS = 16.67 ms   |   30 FPS = 33.3 ms   |   120 FPS = 8.33 ms
The WHOLE frame (CPU sim + render submit + GPU) must fit the budget; the GPU runs in parallel,
so the slower of CPU-frame and GPU-frame sets your FPS. Allocate sub-budgets, e.g. @60 FPS:
  gameplay/scripts ~5 ms · physics ~3 ms · rendering(CPU submit) ~4 ms · UI/other ~2 ms · slack.
If one subsystem blows its slice, that's your target — not whatever you assumed.

Godot 4.x : Debugger ▸ Profiler (script/physics time) and Monitors tab (FPS, draw calls, memory).
            In code: Performance.get_monitor(Performance.TIME_PROCESS) and
            Performance.get_monitor(Performance.RENDER_TOTAL_DRAW_CALLS_IN_FRAME).
Unity 6   : Profiler window (CPU/GPU/Memory/Rendering modules) + Frame Debugger for draw calls.
            In code: a ProfilerRecorder tracking "CPU Main Thread Frame Time" for a HUD/log.
Unreal 5  : `stat unit` (Frame/Game/Draw/GPU ms), `stat fps`, `stat scenerendering` (draw calls);
            Unreal Insights for deep traces.
# Read the split: is the Draw/GPU line the biggest, or the Game/CPU line? That decides the fix.

# Bullets, particles, enemies, damage numbers: reuse a fixed set instead of instantiate()/free()
# every frame — that thrashes memory and (in C#) feeds the GC.
var _pool: Array[Node] = []
func acquire() -> Node:
    var n: Node = _pool.pop_back() if not _pool.is_empty() else bullet_scene.instantiate()
    n.set_process(true); n.visible = true
    return n
func release(n: Node) -> void:
    n.set_process(false); n.visible = false       # disable + hide; DON'T free
    _pool.append(n)                                # back to the pool for reuse
# RIGHT: pre-warm the pool at load; reuse. WRONG: instantiate()/queue_free() per shot.

Each unique material/texture/state change is roughly a draw call; thousands of them stall the GPU.
- Atlas textures and share materials so sprites/meshes batch into one call.
- Identical meshes → GPU instancing (Unity), MultiMesh / MultiMeshInstance (Godot), Instanced
  Static Mesh (Unreal).
- Static geometry → static batching / baking; mark non-moving objects static.
- Reduce overdraw: limit large overlapping transparent/particle layers (they re-shade pixels).
- Fewer real-time lights/shadows; bake lighting where it doesn't move.
Measure draw calls before and after — the count should drop, and so should GPU frame time.

// Unity 6 (C#). Allocating every frame fills the managed heap; the GC then stalls a frame.
// WRONG (allocates each call): foreach (var e in FindObjectsOfType<Enemy>()) ...  // + LINQ, new[]
// RIGHT: cache references once, reuse buffers, avoid LINQ/boxing in Update.
void Update() {
    _hits = Physics.RaycastNonAlloc(ray, _hitBuffer);   // reuse a preallocated array
    for (int i = 0; i < _hits; i++) { /* ... */ }       // no per-frame allocation
}
// Godot/GDScript: avoid building new arrays/dictionaries every frame in _process; reuse them.

© ukanwat, Apache-2.0. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 1 other file (references) in .claude/skills/performance-optimization of ukanwat/overtime.

• SKILL.md
• references/profiling-and-budgets.md

Open the folder on GitHubat commit fc215d4

Used in 1 other repository

We found 1 copy of this SKILL.md (exact, near-identical or edited) in other folders, from 1 other GitHub owner. This page covers the copy in ukanwat/overtime, which our catalogue first saw on October 7, 2026.

• gamedev-skills/awesome-gamedev-agent-skillsskills/disciplines/performance-optimization