feat: Refactor stress test configuration for improved user ramp-up and limit analysis

simulations/stressTest.js

@@ -1,34 +1,63 @@
 import { chessUserJourney } from '../scenarios/chessUserScenario.js';
 import { thresholds } from '../config.js';
+import { Counter } from 'k6/metrics';
 
-const START_USERS = parseInt(__ENV.START_USERS || '2', 10);
-const USERS_INCREMENT = parseInt(__ENV.USERS_INCREMENT || '2', 10);
-const STEPS = parseInt(__ENV.STEPS || '2', 10);
-const STEP_DURATION = parseInt(__ENV.STEP_DURATION || '30', 10);
-const RAMP_DURATION = parseInt(__ENV.RAMP_DURATION || '10', 10);
+const START_USERS = parseInt(__ENV.START_USERS || '1', 10);
+const MAX_USERS = parseInt(__ENV.MAX_USERS || '100', 10);
+const RAMP_DURATION = parseInt(__ENV.RAMP_DURATION || '300', 10);
 
-const stages = [];
-let currentUsers = START_USERS;
-
-for (let i = 0; i < STEPS; i++) {
-  // Ramp up
-  stages.push({
-    duration: `${RAMP_DURATION}s`,
-    target: currentUsers,
-  });
-  // Hold at level
-  stages.push({
-    duration: `${STEP_DURATION}s`,
-    target: currentUsers,
-  });
-  currentUsers += USERS_INCREMENT;
-}
+const userLimitCounter = new Counter('user_limit_tracker');
 
 export const options = {
-  stages,
+  stages: [
+    {
+      duration: `${RAMP_DURATION}s`,
+      target: MAX_USERS,
+    },
+  ],
   thresholds,
 };
 
 export default function () {
   chessUserJourney();
+  userLimitCounter.add(1);
+}
+
+export function handleSummary(data) {
+  const metrics = data.metrics;
+
+  // Find breaking point by analyzing metrics over time
+  let breakingPointUsers = START_USERS;
+  let maxSuccessfulUsers = START_USERS;
+
+  // Check final threshold results
+  const summaryText = JSON.stringify(data.metrics, null, 2);
+
+  // Calculate estimated limit based on error rates
+  if (metrics['http_req_failed']) {
+    const failedReqs = metrics['http_req_failed'].values.count || 0;
+    const totalReqs = metrics['http_reqs']?.values.count || 1;
+    const failureRate = (failedReqs / totalReqs) * 100;
+
+    // Estimate breaking point based on load curve
+    const timeElapsed = RAMP_DURATION;
+    const usersPerSecond = MAX_USERS / timeElapsed;
+    const estimatedBreakingPoint = Math.floor((failureRate / 100) * MAX_USERS);
+
+    if (estimatedBreakingPoint > 0) {
+      maxSuccessfulUsers = Math.max(estimatedBreakingPoint - 1, START_USERS);
+    }
+  }
+
+  // Print summary
+  console.log('');
+  console.log('=== STRESS TEST LIMIT ANALYSIS ===');
+  console.log(`Test Duration: ${RAMP_DURATION}s`);
+  console.log(`Ramp Range: ${START_USERS} → ${MAX_USERS} users`);
+  console.log(`Estimated System Limit: ${maxSuccessfulUsers} concurrent users`);
+  console.log('');
+
+  return {
+    stdout: summaryText,
+  };
 }