anchor.diff:               atom()).
   backend_mod(bitcask) ->
       leo_backend_db_bitcask;
  -backend_mod(leveldb) ->
  -    leo_backend_db_eleveldb;
  +%% backend_mod(leveldb) ->
  +%%     leo_backend_db_eleveldb;
   backend_mod(ets) ->
       leo_backend_db_ets;
   backend_mod(_) ->
  
positive.code:           end,
      Ret = lists:map(Fun, lists:seq(0, NumOfDBProcs-1)),
  
      case whereis(leo_backend_db_sup) of
          undefined ->
              error_logger:error_msg("~p,~p,~p,~p~n",
                                     [{module, ?MODULE_STRING}, {function, "new/4"},
                                      {line, ?LINE}, {body, "NOT started supervisor"}]),
              exit(not_initialized);
          SupRef ->
              case supervisor:count_children(SupRef) of
                  [{specs,_},{active,Active},{supervisors,_},{workers,Workers}] when Active == Workers ->
                      case ets:lookup(?ETS_TABLE_NAME, InstanceName) of
                          [] ->
                              true = ets:insert(?ETS_TABLE_NAME, {InstanceName, Ret});
                          [{InstanceName, List}|_] ->
                              true = ets:delete(?ETS_TABLE_NAME, InstanceName),
                              true = ets:insert(?ETS_TABLE_NAME, {InstanceName, List ++ Ret})
                      end,
                      ok;
                  _ ->
                      error_logger:error_msg("~p,~p,~p,~p~n",
                                             [{module, ?MODULE_STRING}, {function, "new/4"},
                                              {line, ?LINE},
                                              {body, "Could NOT start worker processes"}]),
                      case leo_backend_db_sup:stop() of
                          ok ->
                              exit(invalid_launch);
                          not_started ->
                              exit(noproc)
                      end
              end
      end.
  
  
negative.code:                   ChildSpec = {Id,
                                 {leo_backend_db_server, start_link, Args},
                                 permanent, 2000, worker, [leo_backend_db_server]},
                    case supervisor:start_child(SupRef0, ChildSpec) of
                        {ok, _Pid} ->
                            Id;
                        Cause ->
  