stress-testing

Testing & Quality

Test system behavior under extreme load conditions to identify breaking points, capacity limits, and failure modes. Use for stress test, capacity testing, breaking point analysis, spike test, and system limits validation.

QUICK START

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Overview

Stress testing pushes systems beyond normal operating capacity to identify breaking points, failure modes, and recovery behavior. It validates system stability under extreme conditions and helps determine maximum capacity before degradation or failure.

When to Use

Finding system capacity limits
Identifying breaking points
Testing auto-scaling behavior
Validating error handling under load
Testing recovery after failures
Planning capacity requirements
Verifying graceful degradation
Testing spike traffic handling

Quick Start

Minimal working example:

// stress-test.js
import http from "k6/http";
import { check, sleep } from "k6";
import { Rate } from "k6/metrics";

const errorRate = new Rate("errors");

export const options = {
  stages: [
    // Stress testing: Progressive load increase
    { duration: "2m", target: 100 }, // Normal load
    { duration: "5m", target: 100 }, // Sustain normal
    { duration: "2m", target: 200 }, // Above normal
    { duration: "5m", target: 200 }, // Sustain above normal
    { duration: "2m", target: 300 }, // Breaking point approaching
    { duration: "5m", target: 300 }, // Sustain high load
    { duration: "2m", target: 400 }, // Beyond capacity
    { duration: "5m", target: 400 }, // System under stress
    { duration: "5m", target: 0 }, // Gradual recovery
  ],
  thresholds: {
    http_req_duration: ["p(99)<1000"], // 99% under 1s during stress
    http_req_failed: ["rate<0.05"], // Allow 5% error rate under stress
    errors: ["rate<0.1"],
  },
// ... (see reference guides for full implementation)

Reference Guides

Detailed implementations in the references/ directory:

Guide	Contents
k6 Stress Testing	k6 Stress Testing
Spike Testing	Spike Testing
Soak/Endurance Testing	Soak/Endurance Testing
JMeter Stress Test	JMeter Stress Test
Auto-Scaling Validation	Auto-Scaling Validation
Breaking Point Analysis	Breaking Point Analysis

Best Practices

✅ DO

Test in production-like environment
Monitor all system resources
Gradually increase load to find limits
Test recovery after stress
Document breaking points
Test auto-scaling behavior
Plan for graceful degradation
Monitor for memory leaks

❌ DON'T

Test in production without safeguards
Skip recovery testing
Ignore warning signs (CPU, memory)
Test only success scenarios
Assume linear scalability
Forget database capacity
Skip monitoring third-party dependencies
Test without proper cleanup