Performance Profiler

Comprehensive performance analysis and optimization toolkit

Quick Commands

# CPU profiling
node --inspect app.js
chrome://inspect

# Memory profiling
node --expose-gc --trace-gc app.js

# Bundle size analysis
npx webpack-bundle-analyzer stats.json

# Runtime performance
npx lighthouse http://localhost:3000

Core Functionality

Key Features

1. CPU Profiling: Identify performance hotspots
2. Memory Analysis: Detect leaks and optimize usage
3. Bundle Optimization: Reduce JavaScript payload
4. Network Performance: API and asset loading
5. Rendering Performance: DOM and React optimization

Detailed Information

For comprehensive details, see:

cat .claude/skills/performance-profiler/references/profiling-guide.md

cat .claude/skills/performance-profiler/references/optimization-techniques.md

cat .claude/skills/performance-profiler/references/metrics-explained.md

Usage Examples

Example 1: Profile Application Startup

import { PerformanceProfiler } from '@j0kz/performance-profiler';

const profiler = new PerformanceProfiler();
profiler.start('app-startup');

// Your application initialization
await app.initialize();

const metrics = profiler.stop('app-startup');
console.log(`Startup time: ${metrics.duration}ms`);
console.log(`Memory used: ${metrics.memoryUsed}MB`);

Example 2: Detect Memory Leaks

const leakDetector = profiler.createLeakDetector();

await leakDetector.baseline();
// Perform operations
await leakDetector.snapshot();

const leaks = leakDetector.analyze();
if (leaks.found) {
  console.log('Potential memory leaks:', leaks.suspects);
}

Performance Metrics

Core Web Vitals

• LCP (Largest Contentful Paint): < 2.5s
• FID (First Input Delay): < 100ms
• CLS (Cumulative Layout Shift): < 0.1

Application Metrics

• Time to Interactive (TTI)
• First Contentful Paint (FCP)
• Speed Index
• Total Blocking Time (TBT)

Configuration

{
  "performance-profiler": {
    "targets": {
      "startupTime": 1000,
      "memoryLimit": "256MB",
      "bundleSize": "200KB"
    },
    "sampling": {
      "cpu": 100,
      "memory": 1000
    },
    "reporting": {
      "format": "html",
      "outputDir": "./performance-reports"
    }
  }
}

Integration with Monitoring

// Send metrics to monitoring service
profiler.on('metric', (metric) => {
  monitoring.track(metric.name, metric.value);
});

Notes

• Supports Node.js and browser environments
• Integrates with Chrome DevTools Protocol
• Can generate flamegraphs and memory snapshots
• Automated performance regression detection