Specify devices that improve elapsed time

To get the best elapsed time improvement when using disk with DFSORT, you should use high speed devices, such as IBM's Enterprise Storage Server (ESS) and TotalStorage RS8000 Series subsystems for SORTIN, SORTOUT, SORTWKdd, SORTOUT, and OUTFIL data sets. Throughput can be further improved by leveraging high speed channels, such as IBM's FICON connectivity solutions.