Speeding up tape sorting with overlapped rewinds! This paper describes a variation of the polyphase merge technique for sorting, where one tape can be rewound while the merge operation continues on the remaining tapes. This overlapping of tasks reduces the overall sorting time. The technique is particularly useful when operating on five or more tapes that cannot be read backwards. The savings achieved with this overlap method appear to increase as the number of available tapes rises. This variation of the polyphase merge technique provides a practical approach for optimizing tape-based sorting processes. By overlapping rewind operations, it reduces processing time and improves the efficiency of sorting.
Appearing in Communications of the ACM, this article on polyphase sorting with overlapped rewind is relevant to the journal's focus on algorithms and data processing techniques. The optimization of tape-based sorting contributes to the discussions on efficient data management in computer systems, aligning with the journal’s thematic scope.