Load testing

To keep several cores busy you need concurrent requests, at least as many as WORKERS. With hey:

hey -n 100 -c 8 "http://127.0.0.1:3000/stress?number=40"

With k6, save this as stress.js:

import http from 'k6/http';

export const options = { vus: 8, duration: '60s' };

export default function () {
    http.get('http://127.0.0.1:3000/stress?number=40');
}

and run k6 run stress.js.

With plain curl (8 parallel requests):

for i in $(seq 8); do curl -s "http://127.0.0.1:3000/stress?number=40" & done; wait

Lower or raise number to tune how long each request keeps a core busy.