Agent skill · data analytics · davila7
performance-profiling
Performance profiling principles. Measurement, analysis, and optimization techniques.
Why this skill is useful
Adds a runtime script for automated performance profiling that the AI wouldn't reliably generate on its own.
What it needs
Requires python installed locally. About 2k tokens when loaded. Last updated 2026-08-06. 30,138 stars on the source repository.
What this skill does
Performance Profiling Measure, analyze, optimize - in that order. 🔧 Runtime Scripts Execute these for automated profiling: Script Purpose Usage -------- --------- ------- scripts/lighthouseaudit.py Lighthouse performance audit python scripts/lighthouseaudit.py https://example.com --- 1. Core Web Vitals Targets Metric Good Poor Measures -------- ------ ------ ---------- LCP < 2.5s > 4.0s Loading INP < 200ms > 500ms Interactivity CLS < 0.1 > 0.25 Stability When to Measure Stage Tool ------- ------ Development Local Lighthouse CI/CD Lighthouse CI Production RUM (Real User Monitoring) --- 2. Profiling Workflow The 4-Step Process Profiling Tool Selection Problem Tool --------- ------ Page load Lighthouse Bundle size Bundle analyzer Runtime DevTools Performance Memory DevTools Memory Network DevTools Network --- 3. Bundle Analysis What to Look For Issue Indicator ------- ----------- Large dependencies Top of bundle Duplicate code Multiple chunks Unused code Low coverage Missing splits Single large chunk Optimization Actions Finding Action --------- -------- Big library Import specific modules Duplicate deps Dedupe, update versions Route in main Code split Unused exports Tree shake --- 4. Runtime Profiling Performance Tab Analysis Pattern Meaning --------- --------- Long tasks (>50ms) UI blocking Many small tasks Possible batching opportunity Layout/paint Rendering bottleneck Script JavaScript execution Memory Tab Analysis Pattern Meaning --------- --------- Growing heap Possible leak Large retained Check references Detached DOM Not cleaned up --- 5. Common Bottlenecks By Symptom Symptom Likely Cause --------- -------------- Slow initial load Large JS, render blocking Slow interactions Heavy event handlers Jank during scroll Layout thrashing Growing memory Leaks, retained refs --- 6. …
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills davila7/performance-profiling