An embodiment includes dividing a map into a first grid comprising a first plurality of cells with a first resolution and into a second grid comprising a second plurality of cells with a second resolution; determining that, because an initial portion of a key of a first cell of the second grid comprises a key of a first cell of the first grid, the first cell of the first grid comprises the first cell of the second grid; storing the first and the second grid in memories of distributed servers, wherein the first cell of the first grid and the first cell of the second grid are stored in a same one of the distributed servers or are stored in neighboring ones of the distributed servers; and directing respective processors of the distributed servers to perform a parallel search of the first grid and the second grid using the keys.