Performance Testing

k6 Load Test

  stages: [
    { duration: '30s', target: 20 },   // Ramp up to 20 users
    { duration: '1m', target: 20 },    // Stay at 20 users
    { duration: '30s', target: 0 },    // Ramp down
  ],
  thresholds: {
    http_req_duration: ['p(95)<500'],  // 95% requests under 500ms
    http_req_failed: ['rate<0.01'],    // <1% errors
  },
};

  const res = http.get('http://localhost:3000/api/users');

  check(res, {
    'status is 200': (r) => r.status === 200,
    'response time < 200ms': (r) => r.timings.duration < 200,
  });

  sleep(1);
}

Stress Test

  stages: [
    { duration: '2m', target: 100 },   // Ramp to 100 users
    { duration: '5m', target: 100 },   // Stay at 100
    { duration: '2m', target: 200 },   // Push to 200
    { duration: '5m', target: 200 },   // Stay at 200
    { duration: '2m', target: 0 },     // Ramp down
  ],
};

Spike Test

  stages: [
    { duration: '10s', target: 10 },   // Normal load
    { duration: '1m', target: 10 },
    { duration: '10s', target: 200 },  // Spike!
    { duration: '3m', target: 200 },
    { duration: '10s', target: 10 },   // Scale down
    { duration: '3m', target: 10 },
    { duration: '10s', target: 0 },
  ],
};

API Testing with Auth

  const loginRes = http.post('http://localhost:3000/api/login', {
    email: 'test@test.com',
    password: 'password',
  });
  return { token: loginRes.json('token') };
}

  const params = {
    headers: { Authorization: `Bearer ${data.token}` },
  };

  http.get('http://localhost:3000/api/protected', params);
}

Thresholds Reference

thresholds: {
  // Response time
  http_req_duration: ['p(95)<500', 'p(99)<1000'],

  // Error rate
  http_req_failed: ['rate<0.01'],

  // Throughput
  http_reqs: ['rate>100'],

  // Custom metrics
  'http_req_duration{name:login}': ['p(95)<200'],
}

Quick Reference