Node.js Worker Threads Not Sharing Memory as Expected - Performance Issues
I'm having a hard time understanding After trying multiple solutions online, I still can't figure this out. I am working with Node.js version 18.12.1 and trying to use the Worker Threads module to offload some CPU-intensive tasks. The problem arises when I expect the shared memory buffer to be utilized effectively, but it doesn't seem to work as intended, leading to significant performance issues. I created a shared `ArrayBuffer` to hold data for both the main thread and the worker thread. Here’s a snippet of how I set it up: ```javascript const { Worker, isMainThread, parentPort, SharedArrayBuffer } = require('worker_threads'); const buffer = new SharedArrayBuffer(4 * Int32Array.BYTES_PER_ELEMENT); const sharedArray = new Int32Array(buffer); if (isMainThread) { const worker = new Worker(__filename); // Modify the shared array for (let i = 0; i < 4; i++) { sharedArray[i] = i + 1; console.log(`Main Thread: Setting value ${sharedArray[i]} at index ${i}`); } worker.postMessage(buffer); } else { parentPort.on('message', (buffer) => { const sharedArray = new Int32Array(buffer); for (let i = 0; i < 4; i++) { console.log(`Worker Thread: Value at index ${i} is ${sharedArray[i]}`); } }); } ``` When I run this code, the worker thread logs undefined values instead of the expected numbers. I’ve also tried adding a slight delay using `setTimeout` before reading from the shared array in the worker, but that didn’t solve the issue. I’m not sure if I’m misunderstanding how to properly share memory between threads or if there’s another underlying problem. Any insights or suggestions on how to make this work would be greatly appreciated! Additionally, I've reviewed the documentation on `SharedArrayBuffer` and `Atomics`, but I still feel like I'm missing something crucial regarding memory synchronization. My main goal is to ensure that the worker thread reads the updated values correctly without having to serialize the data each time, so if there are any best practices for handling shared memory in Node.js, I would love to hear them. Has anyone else encountered this? I've been using Javascript for about a year now. I appreciate any insights!