diff --git a/src/vs/code/electron-main/app.ts b/src/vs/code/electron-main/app.ts
index 772bd71bcfc..949eff078cb 100644
--- a/src/vs/code/electron-main/app.ts
+++ b/src/vs/code/electron-main/app.ts
@@ -398,7 +398,7 @@ export class CodeApplication extends Disposable {
 		const windows = appInstantiationService.invokeFunction(accessor => this.openFirstWindow(accessor, electronIpcServer, sharedProcessClient));
 
 		// Post Open Windows Tasks
-		this.afterWindowOpen();
+		appInstantiationService.invokeFunction(this.afterWindowOpen.bind(this));
 
 		// Tracing: Stop tracing after windows are ready if enabled
 		if (this.environmentService.args.trace) {
@@ -714,13 +714,18 @@ export class CodeApplication extends Disposable {
 		return { fileUri: URI.file(path) };
 	}
 
-	private afterWindowOpen(): void {
-
+	private afterWindowOpen(accessor: ServicesAccessor): void {
 		// Signal phase: after window open
 		this.lifecycleMainService.phase = LifecycleMainPhase.AfterWindowOpen;
 
 		// Remote Authorities
 		this.handleRemoteAuthorities();
+
+		// Initialize update service
+		const updateService = accessor.get(IUpdateService);
+		if (updateService instanceof Win32UpdateService || updateService instanceof LinuxUpdateService || updateService instanceof DarwinUpdateService) {
+			updateService.initialize();
+		}
 	}
 
 	private handleRemoteAuthorities(): void {
diff --git a/src/vs/platform/update/electron-main/abstractUpdateService.ts b/src/vs/platform/update/electron-main/abstractUpdateService.ts
index d8bf464fed9..380f553f5d8 100644
--- a/src/vs/platform/update/electron-main/abstractUpdateService.ts
+++ b/src/vs/platform/update/electron-main/abstractUpdateService.ts
@@ -26,7 +26,7 @@ export abstract class AbstractUpdateService implements IUpdateService {
 
 	_serviceBrand: undefined;
 
-	protected readonly url: string | undefined;
+	protected url: string | undefined;
 
 	private _state: State = State.Uninitialized;
 
@@ -49,7 +49,14 @@ export abstract class AbstractUpdateService implements IUpdateService {
 		@IEnvironmentService private readonly environmentService: IEnvironmentService,
 		@IRequestService protected requestService: IRequestService,
 		@ILogService protected logService: ILogService,
-	) {
+	) { }
+
+	/**
+	 * This must be called before any other call. This is a performance
+	 * optimization, to avoid using extra CPU cycles before first window open.
+	 * https://github.com/microsoft/vscode/issues/89784
+	 */
+	initialize(): void {
 		if (!this.environmentService.isBuilt) {
 			return; // updates are never enabled when running out of sources
 		}
@@ -173,6 +180,7 @@ export abstract class AbstractUpdateService implements IUpdateService {
 		if (!this.url) {
 			return Promise.resolve(undefined);
 		}
+
 		return this.requestService.request({ url: this.url }, CancellationToken.None).then(context => {
 			// The update server replies with 204 (No Content) when no
 			// update is available - that's all we want to know.
diff --git a/src/vs/platform/update/electron-main/updateService.darwin.ts b/src/vs/platform/update/electron-main/updateService.darwin.ts
index d25c577b66e..c3f9210c24e 100644
--- a/src/vs/platform/update/electron-main/updateService.darwin.ts
+++ b/src/vs/platform/update/electron-main/updateService.darwin.ts
@@ -36,6 +36,10 @@ export class DarwinUpdateService extends AbstractUpdateService {
 		@ILogService logService: ILogService
 	) {
 		super(lifecycleMainService, configurationService, environmentService, requestService, logService);
+	}
+
+	initialize(): void {
+		super.initialize();
 		this.onRawError(this.onError, this, this.disposables);
 		this.onRawUpdateAvailable(this.onUpdateAvailable, this, this.disposables);
 		this.onRawUpdateDownloaded(this.onUpdateDownloaded, this, this.disposables);
diff --git a/src/vs/platform/update/electron-main/updateService.win32.ts b/src/vs/platform/update/electron-main/updateService.win32.ts
index 8f87787b9e7..7c7948d79b5 100644
--- a/src/vs/platform/update/electron-main/updateService.win32.ts
+++ b/src/vs/platform/update/electron-main/updateService.win32.ts
@@ -69,6 +69,10 @@ export class Win32UpdateService extends AbstractUpdateService {
 		@IFileService private readonly fileService: IFileService
 	) {
 		super(lifecycleMainService, configurationService, environmentService, requestService, logService);
+	}
+
+	initialize(): void {
+		super.initialize();
 
 		if (getUpdateType() === UpdateType.Setup) {
 			/* __GDPR__
@@ -81,7 +85,7 @@ export class Win32UpdateService extends AbstractUpdateService {
 					"target" : { "classification": "SystemMetaData", "purpose": "FeatureInsight" }
 				}
 			*/
-			telemetryService.publicLog('update:win32SetupTarget', { target: product.target });
+			this.telemetryService.publicLog('update:win32SetupTarget', { target: product.target });
 		}
 	}