How many cores should my server have for a cluster of 2 node processes?

Hi allI am thinking of using a node cluster (initially just 2 node processes) for my app.The architecture of my product is like this:----incoming log information----> nginx reverse proxy / load balancer --> node app x2 processes --> rabbitmq worker queue --> another node app x2 processes --> mongodb So as you can see, there are two separate servers containing node apps, and each of these node apps will be spawned twice to help improve performance.My question: If I spawn two node processes (same app), do I need three cores? 1 for the OS, etc., and 1 core for each node process?Or is 2 cores enough?Or is there a better way to do this?Thanks for your help.

Submitted March 02, 2016 at 05:35PM by MEAN_questions