Paging performance can be a dominant factor in a program's running time. Many seemingly efficient data structures and algorithms lose orders of magnitude in performance because they generate an excessive number of page faults. This study shows that tradeoffs exist between average row access speed S/sub r/ (which is defined as the number of row elements retrieved divided by the number of blocks accessed) and average column access speed S/sub c/ (defined similarly). The authors prove that the S/sub r/S/sub c/ product is optimally bounded by the block size N and generalize to other access patterns. Practical array access strategies are developed, and extensions to these results are discussed.>