NODE.JS GUIDE
Node.js Performance Optimization
By the HireReadyAI team · 9 min read
Measure latency and event-loop delay first, then fix CPU hot spots, queries, and caching.
Measure first
Optimization without metrics wastes time. Track p95/p99 latency, event-loop delay, heap used, GC time, DB pool wait, and error rate. Reproduce with realistic concurrency, not a single curl.
CPU and event loop
Find synchronous hot spots: giant JSON, regex backtracking, crypto, tight loops. Move them off the main thread or precompute. Watch for accidental CPU work in middleware that runs on every request.
I/O and data
Most API slowness is downstream: missing indexes, N+1 queries, over-fetching, chatty microservice calls. Fix queries and caching before micro-optimizing JavaScript.
App-level wins
- Cache hot reads with TTLs and invalidation
- Compress responses where CPU trade-off is worth it
- Paginate lists; avoid unbounded result sets
- Use timeouts and circuit breakers on dependencies
- Profile in staging with production-like data shapes