anchor.diff:      map_view(DbName, DDoc, ViewName, Args0, []).
   
   map_view(DbName, DDoc, ViewName, Args0, DbOptions) ->
  +    set_io_priority(DbName, DbOptions),
       Args = fix_skip_and_limit(Args0),
       {ok, Db} = get_or_create_db(DbName, DbOptions),
       VAcc0 = #vacc{db=Db},
  
positive.code:     reduce_view(DbName, DDoc, ViewName, Args0, []).
  
  reduce_view(DbName, DDoc, ViewName, Args0, DbOptions) ->
      Args = fix_skip_and_limit(Args0),
      {ok, Db} = get_or_create_db(DbName, DbOptions),
      VAcc0 = #vacc{db=Db},
  
negative.code: changes(DbName, #changes_args{} = Args, StartSeq, DbOptions) ->
      changes(DbName, [Args], StartSeq, DbOptions);
  changes(DbName, Options, StartVector, DbOptions) ->
      set_io_priority(DbName, DbOptions),
      #changes_args{dir=Dir} = Args = lists:keyfind(changes_args, 1, Options),
      case get_or_create_db(DbName, DbOptions) of
      {ok, Db} ->
  