I was wondering if it makes sense to add the cluster package to a node application deployed using kubernetes requiring one or less cores.

When using the cluster package we usually do something like this:

const cluster = require('cluster');
const http = require('http');
const numCPUs = require('os').cpus().length;

if (cluster.isMaster) {
  masterProcess();
} else {
  childProcess();  
}

function masterProcess() {
  console.log(`Master ${process.pid} is running`);

  for (let i = 0; i < numCPUs; i++) {
    console.log(`Forking process number ${i}...`);
    cluster.fork();
  }

  process.exit();
}

function childProcess() {
  console.log(`Worker ${process.pid} started and finished`);

  process.exit();
}

But it wouldn't make sense to me to use that with say

resources:
      limits:
        cpu: "1"
      requests:
        cpu: "0.5"

since kubernetes will limit the application cpu time any ways, even when using multiple workers. Does that make sense?

I haven't tried this with a load yet.