SharedArrayBuffer for shared memory in Node.js - Mini Project: Build & Apply

Using SharedArrayBuffer for Shared Memory in Node.js

📖 Scenario: You are building a Node.js application that needs to share a simple counter between two worker threads. This counter will be stored in shared memory so both threads can read and update it safely.

🎯 Goal: Create a shared memory buffer using SharedArrayBuffer and use it to share a counter between threads. You will set up the shared buffer, configure a typed array to access it, update the counter, and finally export the shared buffer for use in worker threads.

📋 What You'll Learn

Create a SharedArrayBuffer of 4 bytes

Create an Int32Array view on the shared buffer

Initialize the counter to zero

Export the shared buffer for use in other modules

💡 Why This Matters

🌍 Real World

SharedArrayBuffer is used in Node.js applications to share memory between worker threads efficiently. This is useful for performance-critical tasks like parallel processing or real-time data sharing.

💼 Career

Understanding shared memory and worker threads is important for backend developers working on scalable Node.js applications that require concurrency and performance optimization.

1

Create a SharedArrayBuffer

Create a variable called sharedBuffer and assign it a new SharedArrayBuffer with a size of 4 bytes.

Node.js

// Create a SharedArrayBuffer of 4 bytes
// Your code here

Need a hint?

Use new SharedArrayBuffer(4) to create a buffer that can hold one 32-bit integer.

2

Create an Int32Array view on the shared buffer

Create a variable called sharedArray and assign it a new Int32Array that uses sharedBuffer as its buffer.

Node.js

const sharedBuffer = new SharedArrayBuffer(4);
// Create an Int32Array view on sharedBuffer
// Your code here

Need a hint?

Use new Int32Array(sharedBuffer) to create a typed array view on the shared buffer.

3

Initialize the counter to zero

Set the first element of sharedArray to 0 to initialize the shared counter.

Node.js

const sharedBuffer = new SharedArrayBuffer(4);
const sharedArray = new Int32Array(sharedBuffer);
// Initialize the counter to zero
// Your code here

Need a hint?

Assign 0 to sharedArray[0] to start the counter at zero.

4

Export the shared buffer

Export the sharedBuffer variable using module.exports so it can be imported by worker threads.

Node.js

const sharedBuffer = new SharedArrayBuffer(4);
const sharedArray = new Int32Array(sharedBuffer);
sharedArray[0] = 0;
// Export sharedBuffer
// Your code here

Need a hint?

Use module.exports = { sharedBuffer } to share the buffer with other files.