diff --git a/src/vs/platform/userDataSync/common/userDataSyncStoreService.ts b/src/vs/platform/userDataSync/common/userDataSyncStoreService.ts
index 4f9c272f2ec05805585f9fcdd305234bb0ec5fbb..252d31728a9ddd9ae04854bada97ba2d9f36dcd3 100644
--- a/src/vs/platform/userDataSync/common/userDataSyncStoreService.ts
+++ b/src/vs/platform/userDataSync/common/userDataSyncStoreService.ts
@@ -297,7 +297,7 @@ export class UserDataSyncStoreService extends Disposable implements IUserDataSyn
 
 }
 
-class RequestsSession {
+export class RequestsSession {
 
 	private count: number = 0;
 	private startTime: Date | undefined = undefined;
diff --git a/src/vs/platform/userDataSync/test/common/userDataSyncStoreService.test.ts b/src/vs/platform/userDataSync/test/common/userDataSyncStoreService.test.ts
index e46525cf2d9b2d92df93cb0bf532a1d7a4684752..eca683222d79c680cc801273235beaef73a29ab4 100644
--- a/src/vs/platform/userDataSync/test/common/userDataSyncStoreService.test.ts
+++ b/src/vs/platform/userDataSync/test/common/userDataSyncStoreService.test.ts
@@ -4,11 +4,17 @@
  *--------------------------------------------------------------------------------------------*/
 
 import * as assert from 'assert';
-import { IUserDataSyncStoreService, SyncResource } from 'vs/platform/userDataSync/common/userDataSync';
+import { IUserDataSyncStoreService, SyncResource, UserDataSyncErrorCode, UserDataSyncStoreError } from 'vs/platform/userDataSync/common/userDataSync';
 import { UserDataSyncClient, UserDataSyncTestServer } from 'vs/platform/userDataSync/test/common/userDataSyncClient';
 import { DisposableStore } from 'vs/base/common/lifecycle';
 import { IProductService } from 'vs/platform/product/common/productService';
 import { isWeb } from 'vs/base/common/platform';
+import { RequestsSession } from 'vs/platform/userDataSync/common/userDataSyncStoreService';
+import { NullTelemetryService } from 'vs/platform/telemetry/common/telemetryUtils';
+import { CancellationToken } from 'vs/base/common/cancellation';
+import { IRequestService } from 'vs/platform/request/common/request';
+import { newWriteableBufferStream } from 'vs/base/common/buffer';
+import { timeout } from 'vs/base/common/async';
 
 suite('UserDataSyncStoreService', () => {
 
@@ -316,5 +322,49 @@ suite('UserDataSyncStoreService', () => {
 		assert.notEqual(target.requestsWithAllHeaders[0].headers!['X-User-Session-Id'], undefined);
 	});
 
+});
+
+suite('UserDataSyncRequestsSession', () => {
+
+	const requestService: IRequestService = {
+		_serviceBrand: undefined,
+		async request() { return { res: { headers: {} }, stream: newWriteableBufferStream() }; },
+		async resolveProxy() { return undefined; }
+	};
+
+	test('too many requests are thrown when limit exceeded', () => {
+		const testObject = new RequestsSession(1, 100, requestService, NullTelemetryService);
+		testObject.request({}, CancellationToken.None);
+
+		try {
+			testObject.request({}, CancellationToken.None);
+			assert.fail('Should fail with limit exceeded');
+		} catch (error) {
+			assert.ok(error instanceof UserDataSyncStoreError);
+			assert.equal((<UserDataSyncStoreError>error).code, UserDataSyncErrorCode.LocalTooManyRequests);
+		}
+	});
+
+	test('requests are handled after session is expired', async () => {
+		const testObject = new RequestsSession(1, 100, requestService, NullTelemetryService);
+		testObject.request({}, CancellationToken.None);
+		await timeout(100);
+		testObject.request({}, CancellationToken.None);
+	});
+
+	test('too many requests are thrown after session is expired', async () => {
+		const testObject = new RequestsSession(1, 100, requestService, NullTelemetryService);
+		testObject.request({}, CancellationToken.None);
+		await timeout(100);
+		testObject.request({}, CancellationToken.None);
+
+		try {
+			testObject.request({}, CancellationToken.None);
+			assert.fail('Should fail with limit exceeded');
+		} catch (error) {
+			assert.ok(error instanceof UserDataSyncStoreError);
+			assert.equal((<UserDataSyncStoreError>error).code, UserDataSyncErrorCode.LocalTooManyRequests);
+		}
+	});
 
 });