diff --git a/synapse/handlers/read_marker.py b/synapse/handlers/read_marker.py
index b5b0303d54..5142ae153d 100644
--- a/synapse/handlers/read_marker.py
+++ b/synapse/handlers/read_marker.py
@@ -41,9 +41,9 @@ class ReadMarkerHandler(BaseHandler):
         """
 
         with (yield self.read_marker_linearizer.queue((room_id, user_id))):
-            account_data = yield self.store.get_account_data_for_room(user_id, room_id)
-
-            existing_read_marker = account_data.get("m.fully_read", None)
+            existing_read_marker = yield self.store.get_account_data_for_room_and_type(
+                user_id, room_id, "m.fully_read",
+            )
 
             should_update = True
 
diff --git a/synapse/replication/slave/storage/account_data.py b/synapse/replication/slave/storage/account_data.py
index 6c8d2954d7..355d14ff7c 100644
--- a/synapse/replication/slave/storage/account_data.py
+++ b/synapse/replication/slave/storage/account_data.py
@@ -56,6 +56,10 @@ class SlavedAccountDataStore(TagsWorkerStore, AccountDataWorkerStore, BaseSlaved
                         (row.data_type, row.user_id,)
                     )
                 self.get_account_data_for_user.invalidate((row.user_id,))
+                self.get_account_data_for_room.invalidate((row.user_id, row.room_id,))
+                self.get_account_data_for_room_and_type.invalidate(
+                    (row.user_id, row.room_id, row.account_data_type,),
+                )
                 self._account_data_stream_cache.entity_has_changed(
                     row.user_id, token
                 )
diff --git a/synapse/storage/account_data.py b/synapse/storage/account_data.py
index 466194e96f..e70c9423e3 100644
--- a/synapse/storage/account_data.py
+++ b/synapse/storage/account_data.py
@@ -133,6 +133,7 @@ class AccountDataWorkerStore(SQLBaseStore):
             for row in rows
         })
 
+    @cached(num_args=2)
     def get_account_data_for_room(self, user_id, room_id):
         """Get all the client account_data for a user for a room.
 
@@ -156,6 +157,38 @@ class AccountDataWorkerStore(SQLBaseStore):
             "get_account_data_for_room", get_account_data_for_room_txn
         )
 
+    @cached(num_args=3, max_entries=5000)
+    def get_account_data_for_room_and_type(self, user_id, room_id, account_data_type):
+        """Get the client account_data of given type for a user for a room.
+
+        Args:
+            user_id(str): The user to get the account_data for.
+            room_id(str): The room to get the account_data for.
+            account_data_type (str): The account data type to get.
+        Returns:
+            A deferred of the room account_data for that type, or None if
+            there isn't any set.
+        """
+        def get_account_data_for_room_and_type_txn(txn):
+            content_json = self._simple_select_one_onecol_txn(
+                txn,
+                table="room_account_data",
+                keyvalues={
+                    "user_id": user_id,
+                    "room_id": room_id,
+                    "account_data_type": account_data_type,
+                },
+                retcol="content",
+                allow_none=True
+            )
+
+            return json.loads(content_json) if content_json else None
+
+        return self.runInteraction(
+            "get_account_data_for_room_and_type",
+            get_account_data_for_room_and_type_txn,
+        )
+
     def get_all_updated_account_data(self, last_global_id, last_room_id,
                                      current_id, limit):
         """Get all the client account_data that has changed on the server
@@ -310,6 +343,10 @@ class AccountDataStore(AccountDataWorkerStore):
 
             self._account_data_stream_cache.entity_has_changed(user_id, next_id)
             self.get_account_data_for_user.invalidate((user_id,))
+            self.get_account_data_for_room.invalidate((user_id, room_id,))
+            self.get_account_data_for_room_and_type.prefill(
+                (user_id, room_id, account_data_type,), content,
+            )
 
         result = self._account_data_id_gen.get_current_token()
         defer.returnValue(result)
diff --git a/synapse/storage/events.py b/synapse/storage/events.py
index b63392a6cd..057b1be4d5 100644
--- a/synapse/storage/events.py
+++ b/synapse/storage/events.py
@@ -28,7 +28,7 @@ from synapse.util.logutils import log_function
 from synapse.util.metrics import Measure
 from synapse.api.constants import EventTypes
 from synapse.api.errors import SynapseError
-from synapse.util.caches.descriptors import cached
+from synapse.util.caches.descriptors import cached, cachedInlineCallbacks
 from synapse.types import get_domain_from_id
 
 from canonicaljson import encode_canonical_json
@@ -2033,7 +2033,7 @@ class EventsStore(EventsWorkerStore):
         to_2, so_2 = yield self._get_event_ordering(event_id2)
         defer.returnValue((to_1, so_1) > (to_2, so_2))
 
-    @defer.inlineCallbacks
+    @cachedInlineCallbacks(max_entries=5000)
     def _get_event_ordering(self, event_id):
         res = yield self._simple_select_one(
             table="events",