Only schedule retention eval if there are multiple segments remaining

Author: kjnilsson

src/osiris_retention.erl

@@ -88,7 +88,8 @@ code_change(_OldVsn, State, _Extra) ->
 %%%===================================================================
 %%% Internal functions
 %%%===================================================================
-schedule({eval, Name, _Dir, Specs, _Fun} = Eval, _Result,
+schedule({eval, Name, _Dir, Specs, _Fun} = Eval,
+         {_, _, NumSegmentRemaining},
          #state{scheduled = Scheduled0} = State) ->
     %% we need to check the scheduled map even if the current specs do not
     %% include max_age as the retention config could have changed
@@ -99,9 +100,9 @@ schedule({eval, Name, _Dir, Specs, _Fun} = Eval, _Result,
                     error ->
                         Scheduled0
                 end,
-    case lists:any(fun ({T, _}) -> T == max_age end, Specs) of
+    case lists:any(fun ({T, _}) -> T == max_age end, Specs) andalso
+         NumSegmentRemaining > 1 of
         true ->
-            %% schedule a new eval
             EvalInterval = application:get_env(osiris, retention_eval_interval,
                                                ?DEFAULT_SHEDULED_EVAL_TIME),
             Ref = erlang:send_after(EvalInterval, self(), {'$gen_cast', Eval}),