No device list change cache

synapse/storage/databases/main/devices.py

@@ -164,23 +164,6 @@ def __init__(
             prefilled_cache=user_signature_stream_prefill,
         )
 
-        (
-            device_list_federation_prefill,
-            device_list_federation_list_id,
-        ) = self.db_pool.get_cache_dict(
-            db_conn,
-            "device_lists_outbound_pokes",
-            entity_column="destination",
-            stream_column="stream_id",
-            max_value=device_list_max,
-            limit=10000,
-        )
-        self._device_list_federation_stream_cache = StreamChangeCache(
-            "DeviceListFederationStreamChangeCache",
-            device_list_federation_list_id,
-            prefilled_cache=device_list_federation_prefill,
-        )
-
         if hs.config.worker.run_background_tasks:
             self._clock.looping_call(
                 self._prune_old_outbound_device_pokes, 60 * 60 * 1000
@@ -221,12 +204,6 @@ def _invalidate_caches_for_devices(
                     (row.user_id,)
                 )
 
-            else:
-                # self._device_list_federation_stream_cache.entity_has_changed(
-                #     row.entity, token
-                # )
-                pass
-
     def device_lists_in_rooms_have_changed(
         self, room_ids: StrCollection, token: int
     ) -> None:
@@ -369,19 +346,6 @@ async def get_device_updates_by_remote(
         if from_stream_id == now_stream_id:
             return now_stream_id, []
 
-        # has_changed = self._device_list_federation_stream_cache.has_entity_changed(
-        #     destination, int(from_stream_id)
-        # )
-        # if not has_changed:
-        #     # debugging for https://github.com/matrix-org/synapse/issues/14251
-        #     issue_8631_logger.debug(
-        #         "%s: no change between %i and %i",
-        #         destination,
-        #         from_stream_id,
-        #         now_stream_id,
-        #     )
-        #     return now_stream_id, []
-
         updates = await self.db_pool.runInteraction(
             "get_device_updates_by_remote",
             self._get_device_updates_by_remote_txn,
@@ -2125,13 +2089,6 @@ def _add_device_outbound_poke_to_stream_txn(
         stream_ids: List[int],
         context: Optional[Dict[str, str]],
     ) -> None:
-        for host in hosts:
-            txn.call_after(
-                self._device_list_federation_stream_cache.entity_has_changed,
-                host,
-                stream_ids[-1],
-            )
-
         now = self._clock.time_msec()
         stream_id_iterator = iter(stream_ids)