diff --git a/apps/emqx/test/emqx_persistent_messages_SUITE.erl b/apps/emqx/test/emqx_persistent_messages_SUITE.erl
index e055ce794..dbd4df0ae 100644
--- a/apps/emqx/test/emqx_persistent_messages_SUITE.erl
+++ b/apps/emqx/test/emqx_persistent_messages_SUITE.erl
@@ -23,18 +23,12 @@
 -compile(export_all).
 -compile(nowarn_export_all).
 
--define(NOW,
-    (calendar:system_time_to_rfc3339(erlang:system_time(millisecond), [{unit, millisecond}]))
-).
 -define(DS_SHARD, <<"local">>).
 
 all() ->
     emqx_common_test_helpers:all(?MODULE).
 
 init_per_suite(Config) ->
-    %% avoid inter-suite flakiness...
-    application:stop(emqx),
-    application:stop(emqx_durable_storage),
     TCApps = emqx_cth_suite:start(
         app_specs(),
         #{work_dir => ?config(priv_dir, Config)}
@@ -232,12 +226,8 @@ receive_messages(0, Msgs) ->
 receive_messages(Count, Msgs) ->
     receive
         {publish, Msg} ->
-            receive_messages(Count - 1, [Msg | Msgs]);
-        {deliver, _Topic, Msg} ->
-            receive_messages(Count - 1, [Msg | Msgs]);
-        _Other ->
-            receive_messages(Count, Msgs)
-    after 5000 ->
+            receive_messages(Count - 1, [Msg | Msgs])
+    after 5_000 ->
         Msgs
     end.
 
diff --git a/apps/emqx/test/emqx_persistent_session_SUITE.erl b/apps/emqx/test/emqx_persistent_session_SUITE.erl
index d8736b918..07cfabc70 100644
--- a/apps/emqx/test/emqx_persistent_session_SUITE.erl
+++ b/apps/emqx/test/emqx_persistent_session_SUITE.erl
@@ -267,8 +267,6 @@ receive_messages(Count, Msgs) ->
     receive
         {publish, Msg} ->
             receive_messages(Count - 1, [Msg | Msgs]);
-        {deliver, _Topic, Msg} ->
-            receive_messages(Count - 1, [Msg | Msgs]);
         _Other ->
             receive_messages(Count, Msgs)
     after 5000 ->
@@ -375,26 +373,6 @@ do_publish(Payloads = [_ | _], PublishFun, WaitForUnregister) ->
 do_publish(Payload, PublishFun, WaitForUnregister) ->
     do_publish([Payload], PublishFun, WaitForUnregister).
 
-get_replay_messages(ReplayID) ->
-    DSShard = <<"local">>,
-    case emqx_ds_storage_layer:restore_iterator(DSShard, ReplayID) of
-        {ok, It} ->
-            do_get_replay_messages(It, []);
-        Error ->
-            error({"error restoring iterator", #{error => Error, replay_id => ReplayID}})
-    end.
-
-do_get_replay_messages(It, Acc) ->
-    case emqx_ds_storage_layer:next(It) of
-        {value, Val, NewIt} ->
-            Msg = erlang:binary_to_term(Val),
-            do_get_replay_messages(NewIt, [Msg | Acc]);
-        none ->
-            {ok, lists:reverse(Acc)};
-        {error, Reason} ->
-            {error, Reason}
-    end.
-
 %%--------------------------------------------------------------------
 %% Test Cases
 %%--------------------------------------------------------------------