perf_hooks: add resourcetiming buffer limit

doc/api/perf_hooks.md

@@ -308,6 +308,17 @@ added: v8.5.0
 Returns the current high resolution millisecond timestamp, where 0 represents
 the start of the current `node` process.
 
+### `performance.setResourceTimingBufferSize(maxSize)`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+Sets the global performance resource timing buffer size to the specified number
+of "resource" type performance entry objects.
+
+By default the max buffer size is set to 250.
+
 ### `performance.timeOrigin`
 
 <!-- YAML
@@ -383,6 +394,18 @@ added: v16.1.0
 An object which is JSON representation of the `performance` object. It
 is similar to [`window.performance.toJSON`][] in browsers.
 
+#### Event: `'resourcetimingbufferfull'`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+The `'resourcetimingbufferfull'` event is fired when the global performance
+resource timing buffer is full. Adjust resource timing buffer size with
+`performance.setResourceTimingBufferSize()` or clear the buffer with
+`performance.clearResourceTimings()` in the event listener to allow
+more entries to be added to the performance timeline buffer.
+
 ## Class: `PerformanceEntry`
 
 <!-- YAML

lib/internal/bootstrap/browser.js

@@ -73,8 +73,10 @@ defineOperation(globalThis, 'btoa', buffer.btoa);
 exposeInterface(globalThis, 'Blob', buffer.Blob);
 
 // https://www.w3.org/TR/hr-time-2/#the-performance-attribute
+const perf_hooks = require('perf_hooks');
+exposeInterface(globalThis, 'Performance', perf_hooks.Performance);
 defineReplacableAttribute(globalThis, 'performance',
-                          require('perf_hooks').performance);
+                          perf_hooks.performance);
 
 function createGlobalConsole() {
   const consoleFromNode =

lib/internal/perf/observe.js

@@ -11,6 +11,8 @@ const {
   ArrayPrototypeSort,
   ArrayPrototypeConcat,
   Error,
+  MathMax,
+  MathMin,
   ObjectDefineProperties,
   ObjectFreeze,
   ObjectKeys,
@@ -95,11 +97,17 @@ const kSupportedEntryTypes = ObjectFreeze([
 let markEntryBuffer = [];
 let measureEntryBuffer = [];
 let resourceTimingBuffer = [];
-const kMaxPerformanceEntryBuffers = 1e6;
+let resourceTimingSecondaryBuffer = [];
+const kPerformanceEntryBufferWarnSize = 1e6;
+// https://www.w3.org/TR/timing-entrytypes-registry/#registry
+// Default buffer limit for resource timing entries.
+let resourceTimingBufferSizeLimit = 250;
+let dispatchBufferFull;
+let resourceTimingBufferFullPending = false;
+
 const kClearPerformanceEntryBuffers = ObjectFreeze({
   'mark': 'performance.clearMarks',
   'measure': 'performance.clearMeasures',
-  'resource': 'performance.clearResourceTimings',
 });
 const kWarnedEntryTypes = new SafeMap();
 
@@ -332,30 +340,38 @@ class PerformanceObserver {
   }
 }
 
+/**
+ * https://www.w3.org/TR/performance-timeline/#dfn-queue-a-performanceentry
+ *
+ * Add the performance entry to the interested performance observer's queue.
+ */
 function enqueue(entry) {
   if (!isPerformanceEntry(entry))
     throw new ERR_INVALID_ARG_TYPE('entry', 'PerformanceEntry', entry);
 
   for (const obs of kObservers) {
     obs[kMaybeBuffer](entry);
   }
+}
 
+/**
+ * Add the user timing entry to the global buffer.
+ */
+function bufferUserTiming(entry) {
   const entryType = entry.entryType;
   let buffer;
   if (entryType === 'mark') {
     buffer = markEntryBuffer;
   } else if (entryType === 'measure') {
     buffer = measureEntryBuffer;
-  } else if (entryType === 'resource') {
-    buffer = resourceTimingBuffer;
   } else {
     return;
   }
 
   ArrayPrototypePush(buffer, entry);
   const count = buffer.length;
 
-  if (count > kMaxPerformanceEntryBuffers &&
+  if (count > kPerformanceEntryBufferWarnSize &&
     !kWarnedEntryTypes.has(entryType)) {
     kWarnedEntryTypes.set(entryType, true);
     // No error code for this since it is a Warning
@@ -372,6 +388,59 @@ function enqueue(entry) {
   }
 }
 
+/**
+ * Add the resource timing entry to the global buffer if the buffer size is not
+ * exceeding the buffer limit, or dispatch a buffer full event on the global
+ * performance object.
+ *
+ * See also https://www.w3.org/TR/resource-timing-2/#dfn-add-a-performanceresourcetiming-entry
+ */
+function bufferResourceTiming(entry) {
+  if (resourceTimingBuffer.length < resourceTimingBufferSizeLimit && !resourceTimingBufferFullPending) {
+    ArrayPrototypePush(resourceTimingBuffer, entry);
+    return;
+  }
+
+  if (!resourceTimingBufferFullPending) {
+    resourceTimingBufferFullPending = true;
+    setImmediate(() => {
+      while (resourceTimingSecondaryBuffer.length > 0) {
+        const excessNumberBefore = resourceTimingSecondaryBuffer.length;
+        dispatchBufferFull('resourcetimingbufferfull');
+
+        // Calculate the number of items to be pushed to the global buffer.
+        const numbersToPreserve = MathMax(
+          MathMin(resourceTimingBufferSizeLimit - resourceTimingBuffer.length, resourceTimingSecondaryBuffer.length),
+          0
+        );
+        const excessNumberAfter = resourceTimingSecondaryBuffer.length - numbersToPreserve;
+        for (let idx = 0; idx < numbersToPreserve; idx++) {
+          ArrayPrototypePush(resourceTimingBuffer, resourceTimingSecondaryBuffer[idx]);
+        }
+
+        if (excessNumberBefore <= excessNumberAfter) {
+          resourceTimingSecondaryBuffer = [];
+        }
+      }
+      resourceTimingBufferFullPending = false;
+    });
+  }
+
+  ArrayPrototypePush(resourceTimingSecondaryBuffer, entry);
+}
+
+// https://w3c.github.io/resource-timing/#dom-performance-setresourcetimingbuffersize
+function setResourceTimingBufferSize(maxSize) {
+  // If the maxSize parameter is less than resource timing buffer current
+  // size, no PerformanceResourceTiming objects are to be removed from the
+  // performance entry buffer.
+  resourceTimingBufferSizeLimit = maxSize;
+}
+
+function setDispatchBufferFull(fn) {
+  dispatchBufferFull = fn;
+}
+
 function clearEntriesFromBuffer(type, name) {
   if (type !== 'mark' && type !== 'measure' && type !== 'resource') {
     return;
@@ -492,4 +561,9 @@ module.exports = {
   filterBufferMapByNameAndType,
   startPerf,
   stopPerf,
+
+  bufferUserTiming,
+  bufferResourceTiming,
+  setResourceTimingBufferSize,
+  setDispatchBufferFull,
 };

lib/internal/perf/performance.js

@@ -15,6 +15,8 @@ const {
 
 const {
   EventTarget,
+  Event,
+  kTrustEvent,
 } = require('internal/event_target');
 
 const { now } = require('internal/perf/utils');
@@ -29,6 +31,8 @@ const {
 const {
   clearEntriesFromBuffer,
   filterBufferMapByNameAndType,
+  setResourceTimingBufferSize,
+  setDispatchBufferFull,
 } = require('internal/perf/observe');
 
 const { eventLoopUtilization } = require('internal/perf/event_loop_utilization');
@@ -190,6 +194,12 @@ ObjectDefineProperties(Performance.prototype, {
     enumerable: false,
     value: now,
   },
+  setResourceTimingBufferSize: {
+    __proto__: null,
+    configurable: true,
+    enumerable: false,
+    value: setResourceTimingBufferSize
+  },
   timerify: {
     __proto__: null,
     configurable: true,
@@ -223,7 +233,18 @@ function refreshTimeOrigin() {
   });
 }
 
+const performance = new InternalPerformance();
+
+function dispatchBufferFull(type) {
+  const event = new Event(type, {
+    [kTrustEvent]: true
+  });
+  performance.dispatchEvent(event);
+}
+setDispatchBufferFull(dispatchBufferFull);
+
 module.exports = {
-  InternalPerformance,
+  Performance,
+  performance,
   refreshTimeOrigin
 };

lib/internal/perf/resource_timing.js

@@ -4,7 +4,7 @@
 const { InternalPerformanceEntry } = require('internal/perf/performance_entry');
 const { SymbolToStringTag } = primordials;
 const assert = require('internal/assert');
-const { enqueue } = require('internal/perf/observe');
+const { enqueue, bufferResourceTiming } = require('internal/perf/observe');
 const { Symbol, ObjectSetPrototypeOf } = primordials;
 
 const kCacheMode = Symbol('kCacheMode');
@@ -174,6 +174,7 @@ function markResourceTiming(
 
   ObjectSetPrototypeOf(resource, PerformanceResourceTiming.prototype);
   enqueue(resource);
+  bufferResourceTiming(resource);
   return resource;
 }
 

lib/internal/perf/usertiming.js

@@ -9,7 +9,7 @@ const {
 
 const { InternalPerformanceEntry } = require('internal/perf/performance_entry');
 const { now } = require('internal/perf/utils');
-const { enqueue } = require('internal/perf/observe');
+const { enqueue, bufferUserTiming } = require('internal/perf/observe');
 const nodeTiming = require('internal/perf/nodetiming');
 
 const {
@@ -97,6 +97,7 @@ class PerformanceMeasure extends InternalPerformanceEntry {
 function mark(name, options = kEmptyObject) {
   const mark = new PerformanceMark(name, options);
   enqueue(mark);
+  bufferUserTiming(mark);
   return mark;
 }
 
@@ -161,6 +162,7 @@ function measure(name, startOrMeasureOptions, endMark) {
   detail = detail != null ? structuredClone(detail) : null;
   const measure = new PerformanceMeasure(name, start, duration, detail);
   enqueue(measure);
+  bufferUserTiming(measure);
   return measure;
 }
 

lib/perf_hooks.js

@@ -18,7 +18,10 @@ const {
   PerformanceMark,
   PerformanceMeasure,
 } = require('internal/perf/usertiming');
-const { InternalPerformance } = require('internal/perf/performance');
+const {
+  Performance,
+  performance,
+} = require('internal/perf/performance');
 
 const {
   createHistogram
@@ -27,6 +30,7 @@ const {
 const monitorEventLoopDelay = require('internal/perf/event_loop_delay');
 
 module.exports = {
+  Performance,
   PerformanceEntry,
   PerformanceMark,
   PerformanceMeasure,
@@ -35,7 +39,7 @@ module.exports = {
   PerformanceResourceTiming,
   monitorEventLoopDelay,
   createHistogram,
-  performance: new InternalPerformance(),
+  performance,
 };
 
 ObjectDefineProperty(module.exports, 'constants', {

test/common/index.js

@@ -289,6 +289,9 @@ if (global.gc) {
   knownGlobals.push(global.gc);
 }
 
+if (global.Performance) {
+  knownGlobals.push(global.Performance);
+}
 if (global.performance) {
   knownGlobals.push(global.performance);
 }