diff --git a/tdlib.example.jsonc b/tdlib.example.jsonc
index 275bd64..0df1666 100644
--- a/tdlib.example.jsonc
+++ b/tdlib.example.jsonc
@@ -2,7 +2,8 @@
     "TdlibParameters": { // Detailed information is availabled on https://core.telegram.org/tdlib/docs/classtd_1_1td__api_1_1tdlib_parameters.html
         "api_id": 12345678, // Application identifier for Telegram API access, which can be obtained at https://my.telegram.org.
         "api_hash": "1234567890abcdef0123456789abcdef", // Application identifier hash for Telegram API access, which can be obtained at https://my.telegram.org.
-        "database_directory": "/path/to/database" // Optional. The path to the directory for the persistent database; if empty, the current working directory will be used.
+        "database_directory": "/path/to/database", // Optional. The path to the directory for the persistent database; if empty, the current working directory will be used.
+        "use_message_database": false // Optional. If set to true, the library will maintain a cache of chats and messages. Warn: TdLib do not provide a function to optimize database.
     },
     "encryption_key": "Base64 encoded's key",  // Encryption key to check or set up. Need base64 encoded.
     "proxy": { // Optional. Specify proxy
diff --git a/tdlib.py b/tdlib.py
index 6060642..f54dc81 100644
--- a/tdlib.py
+++ b/tdlib.py
@@ -391,7 +391,7 @@ class TdLib:
             if extra in self._re:
                 re = self._re.pop(extra)
                 return re
-            await asyncio.sleep(0.1)
+            await asyncio.sleep(0.01)
 
     def _update(self):
         result: bytes = _td_json_client_receive(self._client_id, 1.0)
@@ -695,7 +695,7 @@ class TdLib:
             re = await self.receive('updateAuthorizationState')
             state = re['authorization_state']
             if state['@type'] == 'authorizationStateWaitTdlibParameters':
-                pa = {"use_message_database": True,
+                pa = {"use_message_database": False,
                       "system_language_code": "en",
                       "device_model": "Desktop",
                       "application_version": "1.0.0",