This section contains a list of the operating systems supported by DFSORT and an explanation of how DFSORT uses control fields and collating sequences to sort, merge, and copy the records of a data set.

The Blockset technique is DFSORT's most efficient technique for sorting, merging and copying data sets. DFSORT uses the Blockset technique whenever possible to take advantage of its highly optimized internal algorithms and efficient utilization of IBM hardware. If Blockset cannot be used, DFSORT uses another of its techniques — Peerage/Vale or Conventional.