Performance Profiling

Find where your application actually spends time before touching a line of code. Covers the full stack: Node.js CPU and memory profiling, browser flame graphs, React render profiling, and database query analysis. The discipline here is profile first, optimize second — premature optimization is not a workflow, it is a guess.

When to Use

Use for:

• Diagnosing slow Node.js applications (CPU-bound, I/O-bound, memory pressure)
• Generating and reading flame graphs to find hot code paths
• Detecting memory leaks via heap snapshots and growth trends
• Profiling React component render performance with React Profiler
• Measuring browser rendering performance (Core Web Vitals, layout thrashing, long tasks)
• Database query profiling with EXPLAIN ANALYZE
• Measuring event loop utilization and latency

NOT for:

• Infrastructure monitoring, distributed tracing, or log aggregation (use logging-observability)
• Load testing and capacity planning (a separate domain)
• Network latency analysis between services (use distributed tracing tools)