Memory Leaks and Debugging

Monitor Memory

setInterval(() => {
  const used = process.memoryUsage();
  console.log({
    rss: `${Math.round(used.rss / 1024 / 1024)} MB`,
    heapUsed: `${Math.round(used.heapUsed / 1024 / 1024)} MB`
  });
}, 60000);

Common Causes

let cache = {};

emitter.on('data', handler);

function createHandler() {
  const largeData = new Array(1000000);
  return () => {
    console.log(largeData.length);
  };
}

Fixes:

• Use LRU cache with limits
• Remove event listeners
• Don't reference large data in closures

Key Takeaway

Monitor memory in production. Remove event listeners. Use LRU cache with limits. Take heap snapshots to find leaks.