anchor.diff:           }).
   
   -record(state, {
  +          status :: init_in_progress | {init_failed, Reason::term()} | ready,
             qbufs = [] :: [{qbuf_ref(), #qbuf{}}],
             total_size = 0 :: non_neg_integer(),
             %% no new queries; accumulation allowed
  
positive.code: 
  
  -spec handle_cast(term(), #state{}) -> {noreply, #state{}}.
  handle_cast(tick, State) ->
      do_reap_expired_qbufs(State);
  handle_cast(_Msg, State) ->
  
negative.code:     %% don't bother recovering any leftover tables
      case riak_kv_ts_util:rm_rf(RootPath) of
          ok ->
              gen_server:cast(?SERVER, {prepare_qbuf_dir, ok});
          {error, Reason1} ->
              lager:warning("Found old data in qbuf dir \"~s\" could not be removed: ~p", [RootPath, Reason1]),
              gen_server:cast(?SERVER, {prepare_qbuf_dir, ok})
              %% eleveldb:open may fail, users beware
      end,
      case filelib:ensure_dir(RootPath) of
          ok ->
              gen_server:cast(?SERVER, {prepare_qbuf_dir, ok});
          {error, Reason2} ->
              lager:warning("Could not create qbuf dir \"~s\": ~p", [RootPath, Reason2]),
              gen_server:cast(?SERVER, {prepare_qbuf_dir, {fail, Reason2}})
      end.
  
  schedule_tick() ->
  