memory-watch/examples/low-threshold-test.js

Advanced Node.js memory monitoring with stack trace analysis, user code detection, and memory leak identification

const {
  MemoryWatch,
  generateDiagnosticReport,
  getMemoryLeakIndicators,
} = require("../dist/index");

// Test with very low threshold to see immediate results
const watch = new MemoryWatch({
  threshold: 0.3, // 30% threshold - very low for immediate trigger
  interval: 3000, // Check every 3 seconds
  actions: [
    (data) => {
      console.log("\n" + "=".repeat(50));
      console.log("🚨 LOW THRESHOLD TEST - MEMORY ALERT!");
      console.log("=".repeat(50));

      // Show basic info first
      console.log(`📊 Memory Usage: ${(data.percentage * 100).toFixed(1)}%`);
      console.log(
        `💾 Used: ${Math.round(data.usedBytes / 1024 / 1024)}MB / ${Math.round(
          data.totalBytes / 1024 / 1024
        )}MB`
      );

      // Show stack trace - the most important part
      if (data.context?.stackTrace && data.context.stackTrace.length > 0) {
        console.log("\n🔍 STACK TRACE (What caused this):");
        data.context.stackTrace.slice(0, 5).forEach((trace, index) => {
          if (trace.fileName && !trace.fileName.includes("node:")) {
            console.log(
              `   ${index + 1}. 🎯 ${trace.functionName} → ${trace.fileName}:${
                trace.lineNumber
              }`
            );
          } else {
            console.log(`   ${index + 1}. ${trace.functionName}`);
          }
        });
      }

      // Show trigger source
      if (data.context?.triggerSource) {
        console.log(`\n🔎 Trigger: ${data.context.triggerSource}`);
      }

      // Quick memory breakdown
      console.log("\n📈 Memory Details:");
      console.log(
        `   Heap: ${Math.round(data.breakdown.heapUsed / 1024 / 1024)}MB`
      );
      console.log(`   RSS: ${Math.round(data.breakdown.rss / 1024 / 1024)}MB`);
      console.log(
        `   External: ${Math.round(data.breakdown.external / 1024)}KB`
      );

      // Process info
      console.log("\n🖥️  Process:");
      console.log(`   PID: ${data.context?.pid}`);
      console.log(`   Uptime: ${Math.round(data.context?.uptime || 0)}s`);
      console.log(`   Active Handles: ${data.context?.activeHandles}`);

      console.log("=".repeat(50) + "\n");
    },
  ],
});

console.log("🧪 Testing with LOW threshold (30%) for immediate results...");
watch.start();

// Simulate some memory usage
function createSmallMemoryUsage() {
  const data = [];
  for (let i = 0; i < 500; i++) {
    data.push({
      id: i,
      content: new Array(100).fill(`data-${i}`),
    });
  }
  console.log(`📈 Created small memory usage: ${data.length} items`);
  return data;
}

// Create memory usage after 2 seconds
setTimeout(() => {
  console.log("Creating initial memory usage...");
  createSmallMemoryUsage();
}, 2000);

// Stop after 15 seconds
setTimeout(() => {
  watch.stop();
  console.log("✅ Test completed");
  process.exit(0);
}, 15000);