Two-dimensional data is processed and stored in the form of one-dimensional. Different algorithms map 2-dimensional data nodes onto different linear addresses. These diverse addresses lead to various access distances and latencies. Several indicators are proposed in this paper to evaluate the distances made by the 4 major mapping algorithms. The value of these indicators are calculated and analyzed. In many cases

the Z-ordering and Hilbert mapping algorithms can aggregate the neighboring data nodes in a small linear scope. With this feature

increasing prefetch space in cache will enhance the cache hit rate

thereby improve the access speed of the two-dimensional data and optimize system performance.