How to: Q. How to prevent memory leaks in Node.js?
Tools to help debug memory leaks:

**1. Node-heapdump:**

The node-heapdump module is good for post-mortem debugging. It generates heap dumps on your SIGUSR2. To help catch bugs easily in a development environment, add node-heapdump as a dependency to your project like so:

```js
const heapdump = require("heapdump");

heapdump.writeSnapshot(function (err, filename) {
  console.log("Sample dump written to", filename);
});
```

**2. Clinic.js:**

Clinic.js is a handy toolset to diagnose and pinpoint performance bottlenecks in your Node applications. The Clinic.js HeapProfiler uses flame graphs to highlight memory allocations. You can use it with tools such as AutoCannon to simulate HTTP load when profiling.

**3. The process.memoryUsage method:**

The process.memoryUsage method provides a simple way of monitoring memory usage in your Node applications.

The method returns an object with the following properties:

* **rss:**, or resident set size, refers to the amount of space occupied in the main memory for the process, which includes code segment, heap, and stack. If your RSS is going up, there is a likelihood your application is leaking memory
* **heapTotal:**, the total amount of memory available for JavaScript objects
* **heapUsed:**, the total amount of memory occupied by JavaScript objects
* **external:**, the amount of memory consumed by off-heap data (buffers) used by Node; this is where objects, strings, and closures are stored
* **arrayBuffers:**, the amount of memory allocation for ArrayBuffers and SharedArrayBuffers (the external memory size also includes this memory value)

**Example:**

```js
console.log(process.memoryUsage());
```

Output:

```js
{
  rss: 4935680,
  heapTotal:1826816,
  heapUsed:650472,
  external: 49879,
  arrayBuffers: 17310,
}
```

**4. Node Inspector:**

Node Inspector is a debugger interface for Node applications. Run Node with the --inspect flag to use it, and it starts listening for a debugging client. It is one of the simplest ways of capturing heap snapshots with Chrome DevTools.

**5. Chrome DevTools:**

Chrome offers a range of tools to help debug your memory and performance issues, including allocation timelines, sampling heap profiler, and heap snapshots etc.