Abstract: A system for storing sortwork data in a storage subsystem to maximize parallelism during subsequent merging operations. One implementation of the invention employs a computing system with a sort/merge application module and a storage subsystem such as a RAID arrangement. Each DASD unit preferably includes multiple disks in a vertically-stacked array, and each disk is configured with at least one track. Each disk corresponds to one disk of each of the other DASD units. A group of identically-sized locations from identically-positioned tracks of corresponding disks from each DASD unit forms. And, the aggregate of all identically-positioned tracks from all disks in all DASD units makes up a logical array cylinder. To perform sorting and merging operations in accordance with the invention, the sort/merge application module first internally sorts a data packet to generate a string.

Abstract: In a recursive distributive sort of records according to their key fields, a method for distributing keys to form one or more subgroups and collecting them to preserve or maintain an order among the subgroups. The distribution is accomplished by comparing each key field against an extrinsic attribute and then assigning the key to a subgroup or bucket. The collection sequence preserves the overall key field order. A Dynamic Branching Table (DBT) for governing the ordering of buckets during the collection phase is initially populated with NO-OP instructions. During the distribution phase, a CALL instruction replaces the NO-OP in the sorted order DBT position upon the first occurrence of a distinguishable character in the key character sequence being scanned. An address pointer, pointing to the corresponding bucket, is then inserted in a Bucket Pointer Table (BPT) indexed to the DBT.