Backend Latency Profiler Helper

Find and fix API performance bottlenecks.

Slow Endpoint Detection

// Middleware to track latency app.use((req, res, next) => { const start = Date.now();

res.on("finish", () => { const duration = Date.now() - start;

if (duration > 1000) {
  logger.warn(
    {
      endpoint: req.path,
      method: req.method,
      duration_ms: duration,
      userId: req.user?.id,
    },
    "Slow request detected"
  );
}

});

next(); });

Top Slow Endpoints

-- Query from logs SELECT endpoint, AVG(duration_ms) as avg_ms, MAX(duration_ms) as max_ms, COUNT(*) as requests FROM request_logs WHERE created_at > NOW() - INTERVAL '1 day' GROUP BY endpoint HAVING AVG(duration_ms) > 500 ORDER BY avg_ms DESC LIMIT 10;

Suspected Causes

interface PerformanceBottleneck { endpoint: string; avgLatency: number; suspectedCauses: string[]; fixPriority: "high" | "medium" | "low"; }

const bottlenecks: PerformanceBottleneck[] = [ { endpoint: "GET /api/users/:id", avgLatency: 2500, suspectedCauses: [ "N+1 query fetching user orders", "No database index on user_id", "Expensive JSON serialization", ], fixPriority: "high", }, ];

Fix Roadmap

Performance Fix Roadmap

Week 1: Quick Wins

• Add database indexes
• Enable response caching
• Fix N+1 queries

Week 2: Medium Effort

• Optimize slow database queries
• Implement Redis caching
• Add connection pooling

Week 3: Long-term

• Database query optimization
• Service decomposition
• CDN integration

Output Checklist

• Slow endpoints identified

• Causes analyzed

• Fix roadmap created

• Monitoring configured ENDFILE