Files
Claude-Code-Game-Studios/.claude/skills/perf-profile/SKILL.md
Donchitos 70fbf670fc Gap closure: feedback loops, traceability, and new /content-audit skill
- NEW /content-audit skill: GDD-specified content vs implemented content gap
  report with COMPLETE/IN PROGRESS/EARLY/NOT STARTED per system
- balance-check: Fix & Verify Cycle phase (fix → re-verify → propagate-design-change)
- perf-profile: Scope & Timeline Decision phase for M/L effort optimizations
- playtest-report: Action Routing phase categorizes findings → design/balance/bugs/polish
- review-all-gdds: Phase 4 Cross-System Scenario Walkthrough (multi-system sequences)
- story-done: Test-Criterion Traceability (each AC mapped to a test, BLOCKING if >50% untested)
- code-review: ADR Compliance Check (ARCHITECTURAL VIOLATION / ADR DRIFT / MINOR DEVIATION)
- setup-engine: upgrade subcommand (pre-upgrade API scan, migration plan, VERSION.md update)
- story-readiness: Asset References Check (verifies referenced asset paths exist)
- validate-assets.sh: invalid JSON now exits 1 (blocking); naming issues exit 0 (warning)
- workflow-catalog.yaml + sprint-plan: /scope-check wired into production phase

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-03-12 11:18:43 +11:00

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4.8 KiB
Markdown

---
name: perf-profile
description: "Structured performance profiling workflow. Identifies bottlenecks, measures against budgets, and generates optimization recommendations with priority rankings."
argument-hint: "[system-name or 'full']"
user-invocable: true
allowed-tools: Read, Glob, Grep, Bash
---
When this skill is invoked:
1. **Determine scope** from the argument:
- If a system name: focus profiling on that specific system
- If `full`: run a comprehensive profile across all systems
2. **Read performance budgets** — Check for existing performance targets in design docs or CLAUDE.md:
- Target FPS (e.g., 60fps = 16.67ms frame budget)
- Memory budget (total and per-system)
- Load time targets
- Draw call budgets
- Network bandwidth limits (if multiplayer)
3. **Analyze the codebase** for common performance issues:
**CPU Profiling Targets**:
- `_process()` / `Update()` / `Tick()` functions — list all and estimate cost
- Nested loops over large collections
- String operations in hot paths
- Allocation patterns in per-frame code
- Unoptimized search/sort over game entities
- Expensive physics queries (raycasts, overlaps) every frame
**Memory Profiling Targets**:
- Large data structures and their growth patterns
- Texture/asset memory footprint estimates
- Object pool vs instantiate/destroy patterns
- Leaked references (objects that should be freed but aren't)
- Cache sizes and eviction policies
**Rendering Targets** (if applicable):
- Draw call estimates
- Overdraw from overlapping transparent objects
- Shader complexity
- Unoptimized particle systems
- Missing LODs or occlusion culling
**I/O Targets**:
- Save/load performance
- Asset loading patterns (sync vs async)
- Network message frequency and size
4. **Generate the profiling report**:
```markdown
## Performance Profile: [System or Full]
Generated: [Date]
### Performance Budgets
| Metric | Budget | Estimated Current | Status |
|--------|--------|-------------------|--------|
| Frame time | [16.67ms] | [estimate] | [OK/WARNING/OVER] |
| Memory | [target] | [estimate] | [OK/WARNING/OVER] |
| Load time | [target] | [estimate] | [OK/WARNING/OVER] |
| Draw calls | [target] | [estimate] | [OK/WARNING/OVER] |
### Hotspots Identified
| # | Location | Issue | Estimated Impact | Fix Effort |
|---|----------|-------|------------------|------------|
| 1 | [file:line] | [description] | [High/Med/Low] | [S/M/L] |
| 2 | [file:line] | [description] | [High/Med/Low] | [S/M/L] |
### Optimization Recommendations (Priority Order)
1. **[Title]** — [Description of the optimization]
- Location: [file:line]
- Expected gain: [estimate]
- Risk: [Low/Med/High]
- Approach: [How to implement]
### Quick Wins (< 1 hour each)
- [Simple optimization 1]
- [Simple optimization 2]
### Requires Investigation
- [Area that needs actual runtime profiling to determine impact]
```
5. **Output the report** with a summary: top 3 hotspots, estimated headroom vs budget, and recommended next action.
6. **Scope & Timeline Decision** — activate this phase only if any hotspot has Fix Effort rated M or L.
Present a summary of the significant-effort items:
> "The following optimizations require significant effort: [list titles and effort ratings from the Hotspots table]"
For each M/L item, ask the user to choose one of:
- **A) Implement the optimization** (estimated effort: [S/M/L] — proceed with fix now or schedule it)
- **B) Reduce feature scope to avoid the bottleneck** (run `/scope-check [feature]` to analyze the trade-offs)
- **C) Accept the performance hit and defer to Polish phase** (log it as a known issue)
- **D) Escalate to technical-director for an architectural decision** (the bottleneck warrants an ADR)
For choice B, remind the user:
> "Run `/scope-check [feature]` to see what simplifications are available without sacrificing player experience."
For choice D, note:
> "A bottleneck requiring architectural change should become a new Architecture Decision Record. Run `/architecture-decision` to capture the decision and its trade-offs."
If multiple items are deferred to Polish (choice C), record them in the report under a `### Deferred to Polish` section so they are not lost.
### Rules
- Never optimize without measuring first — gut feelings about performance are unreliable
- Recommendations must include estimated impact — "make it faster" is not actionable
- Profile on target hardware, not just development machines
- Distinguish between CPU-bound, GPU-bound, and I/O-bound bottlenecks
- Consider worst-case scenarios (maximum entities, lowest spec hardware, worst network conditions)
- Static analysis (this skill) identifies candidates; runtime profiling confirms