I want to understand how a PM2 deployment will differ from a K8s deployment. I mean with PM2 deployment I would be able to spawn multiple number of processes to utilize all the cores on my server. And with K8s I will basically be giving a single core to every container… ?
Let me help you understand the key differences between PM2 and Kubernetes (K8s) deployments, particularly regarding process/resource management.
Your understanding has a slight misconception that I’ll clarify:
- PM2 (Process Management):
- PM2 is a process manager that runs on a single machine/server
- It can indeed spawn multiple Node.js processes using its cluster mode
- When you use
pm2 start app.js -i max, it creates worker processes based on available CPU cores - All processes share the same host’s resources (memory, disk, network)
- Good for vertical scaling on a single machine
- Kubernetes (K8s):
- This is actually a misconception: K8s containers are NOT limited to single cores by default
- Containers can utilize multiple CPU cores unless explicitly restricted
- You can configure resource requests and limits:
resources: requests: cpu: "1" # Guaranteed minimum of 1 CPU core memory: "1Gi" limits: cpu: "2" # Can use up to 2 CPU cores memory: "2Gi" - K8s provides container orchestration across multiple machines
- Better for horizontal scaling across multiple nodes
Key Differences:
-
Scope:
- PM2: Single server process management
- K8s: Multi-node container orchestration
-
Scalability:
- PM2: Vertical scaling (up on single machine)
- K8s: Both vertical and horizontal scaling (across machines)
-
Resource Management:
- PM2: Shares host resources between processes
- K8s: Can precisely control resource allocation per container
-
Use Cases:
- PM2: Simpler deployments, single-server applications
- K8s: Complex distributed systems, microservices architectures