Initial boiler plate project

node_modules/next/dist/esm/lib/memory/trace.js

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+import v8 from "v8";
+import { info, warn } from "../../build/output/log";
+import { trace } from "../../trace";
+import { bold, italic } from "../picocolors";
+import { join } from "path";
+import { traceGlobals } from "../../trace/shared";
+const HEAP_SNAPSHOT_THRESHOLD_PERCENT = 70;
+let alreadyGeneratedHeapSnapshot = false;
+const TRACE_MEMORY_USAGE_TIMER_MS = 20000;
+let traceMemoryUsageTimer;
+const allMemoryUsage = [];
+/**
+ * Begins a timer that will record memory usage periodically to understand
+ * memory usage across the lifetime of the process.
+ */ export function startPeriodicMemoryUsageTracing() {
+    traceMemoryUsageTimer = setTimeout(()=>{
+        traceMemoryUsage("periodic memory snapshot");
+        startPeriodicMemoryUsageTracing();
+    }, TRACE_MEMORY_USAGE_TIMER_MS);
+}
+export function stopPeriodicMemoryUsageTracing() {
+    if (traceMemoryUsageTimer) {
+        clearTimeout(traceMemoryUsageTimer);
+    }
+}
+/**
+ * Returns the list of all recorded memory usage snapshots from the process.
+ */ export function getAllMemoryUsageSpans() {
+    return allMemoryUsage;
+}
+/**
+ * Records a snapshot of memory usage at this moment in time to the .next/trace
+ * file.
+ */ export function traceMemoryUsage(description, parentSpan) {
+    const memoryUsage = process.memoryUsage();
+    const v8HeapStatistics = v8.getHeapStatistics();
+    const heapUsed = v8HeapStatistics.used_heap_size;
+    const heapMax = v8HeapStatistics.heap_size_limit;
+    const tracedMemoryUsage = {
+        "memory.rss": memoryUsage.rss,
+        "memory.heapUsed": heapUsed,
+        "memory.heapTotal": memoryUsage.heapTotal,
+        "memory.heapMax": heapMax
+    };
+    allMemoryUsage.push(tracedMemoryUsage);
+    const tracedMemoryUsageAsStrings = Object.fromEntries(Object.entries(tracedMemoryUsage).map(([key, value])=>[
+            key,
+            String(value)
+        ]));
+    if (parentSpan) {
+        parentSpan.traceChild("memory-usage", tracedMemoryUsageAsStrings);
+    } else {
+        trace("memory-usage", undefined, tracedMemoryUsageAsStrings);
+    }
+    if (process.env.EXPERIMENTAL_DEBUG_MEMORY_USAGE) {
+        const percentageHeapUsed = 100 * heapUsed / heapMax;
+        info("");
+        info("***************************************");
+        info(`Memory usage report at "${description}":`);
+        info(` - RSS: ${(memoryUsage.rss / 1024 / 1024).toFixed(2)} MB`);
+        info(` - Heap Used: ${(heapUsed / 1024 / 1024).toFixed(2)} MB`);
+        info(` - Heap Total Allocated: ${(memoryUsage.heapTotal / 1024 / 1024).toFixed(2)} MB`);
+        info(` - Heap Max: ${(heapMax / 1024 / 1024).toFixed(2)} MB`);
+        info(` - Percentage Heap Used: ${percentageHeapUsed.toFixed(2)}%`);
+        info("***************************************");
+        info("");
+        if (percentageHeapUsed > HEAP_SNAPSHOT_THRESHOLD_PERCENT) {
+            const distDir = traceGlobals.get("distDir");
+            const heapFilename = join(distDir, `${description.replace(" ", "-")}.heapsnapshot`);
+            warn(bold(`Heap usage is close to the limit. ${percentageHeapUsed.toFixed(2)}% of heap has been used.`));
+            if (!alreadyGeneratedHeapSnapshot) {
+                warn(bold(`Saving heap snapshot to ${heapFilename}.  ${italic("Note: this will take some time.")}`));
+                v8.writeHeapSnapshot(heapFilename);
+                alreadyGeneratedHeapSnapshot = true;
+            } else {
+                warn("Skipping heap snapshot generation since heap snapshot has already been generated.");
+            }
+        }
+    }
+}
+
+//# sourceMappingURL=trace.js.map