Handling Concurrent HTTP Requests with Node.js and Axios in a Loop Causes Excessive Memory Usage
I'm dealing with I'm updating my dependencies and I'm working on a personal project and I'm stuck on something that should probably be simple. I'm currently working on a Node.js application that uses Axios to make multiple concurrent HTTP requests inside a loop. I noticed that when I trigger a batch of requests, the application starts consuming an excessive amount of memory, and eventually crashes with an 'out of memory' error. The requests are being made to an external API that returns a large JSON payload. I've tried using `Promise.all` to manage the requests, but the memory consumption remains high. Here's a simplified version of my code: ```javascript const axios = require('axios'); async function fetchData(ids) { const requests = ids.map(id => axios.get(`https://api.example.com/data/${id}`)); try { const responses = await Promise.all(requests); return responses.map(response => response.data); } catch (error) { console.error('Error fetching data:', error); } } const ids = Array.from({ length: 1000 }, (_, i) => i + 1); // Fetch data for 1000 IDs fetchData(ids); ``` I also tried reducing the number of concurrent requests by using a simple throttle mechanism, but the memory issue persists. Here's the throttling implementation I tested: ```javascript const axios = require('axios'); const pLimit = require('p-limit'); const limit = pLimit(10); // Limit to 10 concurrent requests async function fetchData(ids) { const requests = ids.map(id => limit(() => axios.get(`https://api.example.com/data/${id}`))); try { const results = await Promise.all(requests); return results.map(result => result.data); } catch (error) { console.error('Error fetching data:', error); } } const ids = Array.from({ length: 1000 }, (_, i) => i + 1); fetchData(ids); ``` Despite these changes, the memory usage is still climbing. I'm using Node.js v16.13.0 and have not set any specific memory limits for the process. Could this be due to the large payloads I am receiving from the API, or is there something in my code that I'm missing? How can I effectively manage memory in this scenario? What's the best practice here? Has anyone else encountered this? Am I approaching this the right way? For reference, this is a production microservice. What are your experiences with this?