Marie Cruz
Marie is a software tester and also a tech blogger at testingwithmarie.com where she talks about testing and test automation in general. Currently, she works as a Developer Advocate for k6.io
Introduction to k6.io
How to use k6 for performance testing
agenda
but first..
why performance testing?
We use technology on a daily basis and have been accustomed to instant gratification.
“While customers will forgive and forget the odd bug, crash, or period of site maintenance, they will not tolerate a site that doesn't move at the speed they’ve become accustomed to.”
- Dr. John Bates, CEO, Eggplant from Slow Websites Are Silent Killers for Businesses
Performance Testing
Front End/Client Side
Back End/Server Side
types of performance test
- Load testing
- Soak testing
- Stress testing
What is k6?
k6 is a developer-centric, free and open-source load testing tool built for making performance testing a productive and enjoyable experience - k6 docs
k6 services
k6 open source
k6 cloud
Why was k6 created?
-
Tests written in JavaScript
-
Flexible
-
Test scripting (load testing as code)
-
Test recording
-
Integrates well with CI/CD pipelines
-
Test visualisation with New Relic, Grafana and others!
k6
import http from 'k6/http';
import { sleep } from 'k6';
export default function () {
http.get('https://test.k6.io');
sleep(1);
}
-
Virtual Users (VUs)
-
Metrics
-
Checks
-
Thresholds
k6 key concepts
virtual users
export const options = {
vus: 10,
duration: '1h',
};
export const options = {
stages: [
{ duration: '1m', target: 10 },
{ duration: '1m', target: 20 },
{ duration: '1m', target: 0 },
]
};
export default function () {
http.get('http://test.k6.io/');
}
metrics
running (00m03.8s), 0/1 VUs, 1 complete and 0 interrupted iterations
default ✓ [======================================] 1 VUs 00m03.8s/10m0s 1/1 iters, 1 per VU
data_received..................: 22 kB 5.7 kB/s
data_sent......................: 742 B 198 B/s
http_req_blocked...............: avg=1.05s min=1.05s med=1.05s max=1.05s p(90)=1.05s p(95)=1.05s
http_req_connecting............: avg=334.26ms min=334.26ms med=334.26ms max=334.26ms p(90)=334.26ms p(95)=334.26ms
http_req_duration..............: avg=2.7s min=2.7s med=2.7s max=2.7s p(90)=2.7s p(95)=2.7s
{ expected_response:true }...: avg=2.7s min=2.7s med=2.7s max=2.7s p(90)=2.7s p(95)=2.7s
http_req_failed................: 0.00% ✓ 0 ✗ 1
http_req_receiving.............: avg=112.41µs min=112.41µs med=112.41µs max=112.41µs p(90)=112.41µs p(95)=112.41µs
http_req_sending...............: avg=294.48µs min=294.48µs med=294.48µs max=294.48µs p(90)=294.48µs p(95)=294.48µs
http_req_tls_handshaking.......: avg=700.6ms min=700.6ms med=700.6ms max=700.6ms p(90)=700.6ms p(95)=700.6ms
http_req_waiting...............: avg=2.7s min=2.7s med=2.7s max=2.7s p(90)=2.7s p(95)=2.7s
http_reqs......................: 1 0.266167/s
iteration_duration.............: avg=3.75s min=3.75s med=3.75s max=3.75s p(90)=3.75s p(95)=3.75s
iterations.....................: 1 0.266167/s
vus............................: 1 min=1 max=1
vus_max........................: 1 min=1 max=1checks
import { check } from 'k6';
import http from 'k6/http';
export default function () {
const res = http.get('http://test.k6.io/');
check(res, {
'is status 200': (r) => r.status === 200,
});
}
k6 run script.js
...
✓ is status 200
...
checks.........................: 100.00% ✓ 1 ✗ 0
data_received..................: 11 kB 12 kB/s
thresholds
import http from 'k6/http';
export const options = {
thresholds: {
http_req_failed: ['rate<0.01'], // http errors should be less than 1%
http_req_duration: ['p(95)<200'], // 95% of requests should be below 200ms
},
};
export default function () {
http.get('https://test-api.k6.io/public/crocodiles/1/');
}
-
Tests written in JavaScript
-
Load generation distribution not included in the open source version
-
Node JS libraries not compatible with k6
-
TypeScript support requires a lot of boilerplate so might not be ideal if you want something quick
limitations
demonstration
questions?
Introduction to k6.io
How to use k6 for load testing
Introduction to k6
By Marie Cruz
