Containerized Node.js application showing inconsistent performance on Ubuntu 22.04 staging environment
I'm sure I'm missing something obvious here, but I tried several approaches but none seem to work... After trying multiple solutions online, I still can't figure this out. Currently developing a prototype for a new feature in our Node.js application deployed in Docker containers on Ubuntu 22.04. The goal is to ensure that our staging environment mirrors production as closely as possible, but I've hit a snag. Performance metrics sometimes indicate significant latency, especially during peak load testing with multiple concurrent requests. In configuring the Docker containers, I allocated resources using a `docker-compose.yml` file like this: ```yaml version: '3.8' services: app: image: my-node-app:latest build: context: . ports: - '3000:3000' environment: NODE_ENV: production deploy: resources: limits: cpus: '1.0' memory: 512M ``` However, when I run `docker stats`, I notice the memory usage spikes, occasionally maxing out, but the system itself shows available memory. This inconsistency raises questions about how Docker manages resources and whether my configurations are optimal. I also tried tuning the Node.js application with the `--max-old-space-size` flag: ```bash node --max-old-space-size=256 app.js ``` Despite these adjustments, the response time fluctuates wildly between 50ms to over 500ms during load testing using Artillery. Digging deeper, I've explored potential issues with the underlying database connections, but they appear stable. Particularly, I’m leveraging PostgreSQL with a connection pool set to handle 10 concurrent connections: ```javascript const { Pool } = require('pg'); const pool = new Pool({ max: 10, connectionString: process.env.DATABASE_URL, }); ``` It’s perplexing because network latency seems fine; our load balancer performs adequately with minimal error rates. I also set up a monitoring solution with Prometheus and Grafana, and there are no clear indicators showing bottlenecks. Would appreciate insights on optimizing the Docker setup or suggestions on diagnosing this performance issue. Are there specific flags or configurations I might be missing? Any best practices for ensuring consistent performance in such environments would be invaluable. Any ideas what could be causing this? My development environment is Ubuntu. I'd really appreciate any guidance on this. For context: I'm using Javascript on Windows. What am I doing wrong?