Prefetching with multiple disks for external mergesort: simulation and analysis

The authors present a simulation study of multiple disk systems to improve the input/output (I/O) performance of multiway merging. With the increase in the size of main memory in computer systems, multiple disks and aggressive prefetching can be used to significantly reduce I/O time. Two prefetching strategies-intra-run and inter-run-for external merging using multiple disks were studied. Their performance was evaluated, and simple analytical expressions are derived to explain their asymptotic behavior. The results indicate that a combination of the strategies can result in a significant reduction in I/O time