chore(instrumentation-runtime-node): fix event loop utilization collector

Author: pikalovArtemN

plugins/node/instrumentation-runtime-node/package.json

@@ -39,13 +39,13 @@
     "access": "public"
   },
   "dependencies": {
-    "@opentelemetry/instrumentation": "^0.53.0"
+    "@opentelemetry/instrumentation": "^0.53.0",
   },
   "devDependencies": {
     "@opentelemetry/api": "^1.3.0",
     "@opentelemetry/sdk-metrics": "^1.20.0",
     "@types/mocha": "^10.0.6",
-    "@types/node": "^22.1.0",
+    "@types/node": "^18.18.14",
     "mocha": "7.2.0",
     "nyc": "^15.1.0",
     "rimraf": "5.0.10",

plugins/node/instrumentation-runtime-node/src/global.d.ts

@@ -0,0 +1,21 @@
+import {Histogram} from "perf_hooks";
+
+declare module 'node:perf_hooks' {
+  interface IntervalHistogram extends Histogram {
+    /**
+     * Enables the update interval timer. Returns `true` if the timer was
+     * started, `false` if it was already started.
+     * @since v11.10.0
+     */
+    enable(): boolean;
+
+    /**
+     * Disables the update interval timer. Returns `true` if the timer was
+     * stopped, `false` if it was already stopped.
+     * @since v11.10.0
+     */
+    disable(): boolean;
+
+    count: number;
+  }
+}

plugins/node/instrumentation-runtime-node/src/metrics/eventLoopUtilizationCollector.ts

@@ -23,6 +23,8 @@ const { eventLoopUtilization: eventLoopUtilizationCollector } = performance;
 export const NODEJS_EVENT_LOOP_UTILIZATION = 'eventloop.utilization';
 
 export class EventLoopUtilizationCollector extends BaseCollector {
+  private _lastValue?: EventLoopUtilization;
+
   constructor(
     config: RuntimeNodeInstrumentationConfig = {},
     namePrefix: string
@@ -42,16 +44,13 @@ export class EventLoopUtilizationCollector extends BaseCollector {
       .addCallback(async observableResult => {
         if (!this._config.enabled) return;
 
-        const elu = eventLoopUtilizationCollector(this.scrape());
+        const elu = eventLoopUtilizationCollector(this._lastValue);
         observableResult.observe(elu.utilization);
+        this._lastValue = elu;
       });
   }
 
   protected internalDisable(): void {}
 
   protected internalEnable(): void {}
-
-  private scrape(): EventLoopUtilization {
-    return eventLoopUtilizationCollector();
-  }
 }