Grafana k6 OSS: Demo & Lab

README.md

Here’s a clean, copy-paste-ready beginner tutorial to install Grafana k6 OSS on Windows, write a “Hello World” load test, run it, and understand the results.

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1. Install k6 on Windows

You have a few options. I’ll show the two easiest:

Option A – Using winget (recommended if available)

1. Open Windows Terminal / PowerShell as Administrator.

2. Run:

   winget install grafana.k6

3. After install, verify:

   k6 version

   You should see something like:

   k6 v0.xx.x
   

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Option B – Using Chocolatey

If you’re already using Chocolatey:

1. Open PowerShell (Admin).

2. Install:

   choco install k6

3. Verify:

   k6 version

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Option C – Portable (ZIP) Binary (no package manager)

1. Go to: https://github.com/grafana/k6/releases (in your browser).

2. Download the latest Windows x64 .zip.

3. Extract it to a folder, e.g.:

   C:\tools\k6\
   

4. Add that folder to your PATH:

   • Press Win → search Environment Variables → “Edit the system environment variables”.

   • Click Environment Variables…

   • Under User variables or System variables, select Path → Edit → New → add:

     C:\tools\k6\
     

   • Click OK several times.

5. Open a new PowerShell and run:

   k6 version

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2. Create a Project Folder

Let’s keep things clean.

1. Choose a workspace folder, e.g.:

   mkdir C:\k6-demo
   cd C:\k6-demo

2. You’ll put all your k6 scripts here.

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3. Your First “Hello World” k6 Script

We’ll create a very simple script that:

• Sends 1 HTTP GET request to a test URL.
• Checks that the response status is 200.
• Prints basic stats at the end.

3.1 Create the script file

1. In C:\k6-demo, create a file named hello-world.js.

If you like using Notepad:

notepad .\hello-world.js

Paste this code inside:

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

export const options = {
  vus: 1,          // number of virtual users
  duration: '10s', // total test duration
};

export default function () {
  // 1) Make a simple GET request
  const res = http.get('https://test.k6.io');

  // 2) Validate response
  check(res, {
    'status is 200': (r) => r.status === 200,
  });

  // 3) Small pause between iterations
  sleep(1);
}

Save and close the file.

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4. Run the Hello World Test

From inside the folder:

cd C:\k6-demo
k6 run .\hello-world.js

You will see something like:

          /\      |‾‾| /‾‾/  /‾‾/
     /\  /  \     |  |/  /  /  /
    /  \/    \    |     (  /  /
   /          \   |  |\  \/  /
  / __________ \  |__| \____/

  execution: local
     script: hello-world.js
     output: -

  scenarios: (100.00%) 1 scenario, 1 max VUs, 10s max duration (incl. graceful stop):
           * default: 1 looping VUs for 10s (gracefulStop: 30s)

running (10.0s), 0/1 VUs, 10 complete and 0 interrupted iterations
default ✓ [======================================] 1 VUs  10s

     ✓ status is 200

     checks...................: 100.00% ✓ 10 ✗ 0
     http_req_duration........: avg=150ms min=120ms max=200ms ...
     http_reqs................: 10  (1.0/s)
     vus......................: 1

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5. Understand the Output

Important fields to understand:

• checks – shows how many checks passed/failed:

  • ✓ 10 ✗ 0 → all 10 requests returned status 200.

• http_req_duration – time it took to complete each HTTP request.

  • avg, min, max, percentiles.

• http_reqs – total number of HTTP requests (10 here).

• vus – how many virtual users were active (1 here).

Since status is 200 is the only check, if the website failed or returned a different code, you’d see failed checks.

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6. Slightly More Interesting Example (Hello World with Threshold)

Now, let’s add a threshold so the test “fails” if latency is too high.

Create another file: hello-with-threshold.js

notepad .\hello-with-threshold.js

Paste:

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

export const options = {
  vus: 2,
  duration: '15s',
  thresholds: {
    // 95% of all requests must finish below 500ms
    http_req_duration: ['p(95) < 500'],
    // At least 99% of checks must pass
    checks: ['rate > 0.99'],
  },
};

export default function () {
  const res = http.get('https://test.k6.io');

  check(res, {
    'status is 200': (r) => r.status === 200,
  });

  sleep(1);
}

Run it:

k6 run .\hello-with-threshold.js

At the end, you’ll see something like:

   checks................: 100.00% ✓ 30 ✗ 0
   http_req_duration.....: p(95)=180ms ...
   thresholds:
     * http_req_duration  p(95)<500       ✓  passed
     * checks             rate>0.99       ✓  passed

If you intentionally use a slow or broken URL, you might see thresholds marked as failed with ✗.

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7. Running a Quick “Smoke Test” Style Hello World

If you just want to quickly confirm your script works (like a smoke test):

Create hello-smoke.js:

notepad .\hello-smoke.js

Paste:

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

export const options = {
  vus: 1,
  iterations: 1, // run only once
};

export default function () {
  const res = http.get('https://test.k6.io');
  console.log(`Response status: ${res.status}`);
  sleep(1);
}

Run:

k6 run .\hello-smoke.js

You’ll see a log line:

INFO[0000] Response status: 200

This is a super basic “Hello World” just to embed k6 in a CI step or script.

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8. Typical Folder Structure for Your k6 Work

If you continue learning, you might organize like:

C:\k6-demo
 ├─ hello-world.js
 ├─ hello-with-threshold.js
 ├─ hello-smoke.js
 ├─ scenarios/
 │   ├─ basic-load.js
 │   ├─ spike-test.js
 ├─ data/
 │   └─ users.csv

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9. Next Easy Steps After Hello World

Once this works, good next things to explore:

1. Increase load Change:

   vus: 10,
   duration: '30s',

2. Add multiple URLs Use group() blocks and multiple http.get calls.

3. Export results to JSON (for later analysis):

   k6 run --out json=results.json .\hello-world.js

4. Integrate with Grafana later (Prometheus or k6 Cloud), once you’re comfortable.

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If you tell me:

• Your Windows version (e.g. Windows 10/11), and
• Whether you prefer PowerShell or Command Prompt

I can give you an even more tailored, copy-paste script that:

• Installs k6
• Creates all 3 hello-world scripts
• Runs them one by one automatically.