Node.js Performance Optimization: Tips and Techniques

Why Performance Matters

Performance directly impacts user experience and costs. A well-optimized Node.js application can handle more requests with fewer resources.

Profiling Your Application

Using the Built-in Profiler

node --prof app.js
node --prof-process isolate-*.log > processed.txt

Performance Hooks

const { performance, PerformanceObserver } = require('perf_hooks');

const obs = new PerformanceObserver((items) => {
  console.log(items.getEntries());
});
obs.observe({ entryTypes: ['measure'] });

performance.mark('start');
// Your code here
performance.mark('end');
performance.measure('Operation', 'start', 'end');

Caching Strategies

In-Memory Caching

const NodeCache = require('node-cache');
const cache = new NodeCache({ stdTTL: 600 });

async function getData(key) {
  const cached = cache.get(key);
  if (cached) return cached;
  
  const data = await fetchFromDatabase(key);
  cache.set(key, data);
  return data;
}

Redis for Distributed Caching

const Redis = require('ioredis');
const redis = new Redis();

async function getCachedData(key) {
  const cached = await redis.get(key);
  if (cached) return JSON.parse(cached);
  
  const data = await fetchData(key);
  await redis.setex(key, 3600, JSON.stringify(data));
  return data;
}

Clustering

Utilize all CPU cores:

const cluster = require('cluster');
const os = require('os');

if (cluster.isMaster) {
  const numCPUs = os.cpus().length;
  
  for (let i = 0; i < numCPUs; i++) {
    cluster.fork();
  }
} else {
  require('./app');
}

Database Optimization

Connection Pooling

const { Pool } = require('pg');

const pool = new Pool({
  max: 20,
  idleTimeoutMillis: 30000,
});

async function query(text, params) {
  const client = await pool.connect();
  try {
    return await client.query(text, params);
  } finally {
    client.release();
  }
}

Query Optimization

• Use indexes appropriately
• Avoid N+1 queries
• Use pagination for large datasets
• Consider read replicas

Conclusion

Performance optimization is an ongoing process. Profile first, then optimize the bottlenecks that matter most.

---

Need help optimizing your Node.js application? Contact us for a performance audit.