anchor.diff:  
   -define(EXPENSIVE_CHECK_INTERVAL, 15000). % In ms
   
  --export([start_link/0, status_all/0, expensive_checks/0]).
  +-export([start_link/0, status_all/0, expensive_checks/0, force_beat/0]).
   -export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2,
            code_change/3]).
   
  
positive.code:     {noreply, NewState};
  handle_info(do_expensive_checks, State) ->
      {noreply, State#state{expensive_checks_result = expensive_checks()}};
  handle_info(buckets_event, State) ->
      {noreply, arm_forced_beat_timer(State)};
  handle_info(_, State) ->
      {noreply, State}.
  
negative.code:                         fun (Event, _) ->
                                  case is_interesting_buckets_event(Event) of
                                      true ->
                                          Self ! force_beat;
                                      _ -> ok
                                  end
                          end, []),
      {ok, #state{}}.
  
  force_beat() ->
      ?MODULE ! force_beat.
  
  arm_forced_beat_timer(#state{forced_beat_timer = TRef} = State) when TRef =/= undefined ->
      State;
  