Instant load increase

One of the common usages of load testing tools it’s the so-called stepped arrival rate.

In k6, you can do that by using the options object, and configuring the number of iterations or VUs in different scenarios.

Here’s an example on how to instantly increase the number of iterations and hold them for a period of time.

import http from 'k6/http';
import { sleep } from 'k6';

export const options = {
  scenarios: {
    contacts: {
      executor: 'ramping-arrival-rate',
      preAllocatedVUs: 50,
      timeUnit: '1s',
      startRate: 50,
      stages: [
        { target: 200, duration: '30s' }, // linearly go from 50 iters/s to 200 iters/s for 30s
        { target: 500, duration: '0' }, // instantly jump to 500 iters/s
        { target: 500, duration: '10m' }, // continue with 500 iters/s for 10 minutes
      ],
    },
  },
};

export default function () {
  http.get('https://test.k6.io');
  sleep(1);
}

Here’s an example on how to instantly increase the number of VUs and hold them for a period of time.

import http from 'k6/http';
import { sleep } from 'k6';

export const options = {
  scenarios: {
    contacts: {
      executor: 'ramping-vus',
      startVUs: 3,
      stages: [
        { target: 20, duration: '30s' }, // linearly go from 3 VUs to 20 VUs for 30s
        { target: 100, duration: '0' }, // instantly jump to 100 VUs
        { target: 100, duration: '10m' }, // continue with 100 VUs for 10 minutes
      ],
    },
  },
};

export default function () {
  http.get('https://test.k6.io');
  sleep(1);
}