Disk work data set coding notes

Data sets must be physical sequential; they cannot be partitioned or extended format.
The SPLIT cylinder parameter must not be specified.
If no secondary allocation is requested for temporary SORTWKdd data sets, automatic secondary allocation will be used unless NOWRKSEC is in effect. (Secondary allocation is limited to 12 work data sets in the Peerage and Vale sorting techniques only.)
If the data set is allocated to VIO, there is no automatic secondary allocation.
Secondary allocation can be requested for work data sets. For the Peerage and Vale sorting techniques only, secondary allocation is limited to the first 12 work data sets; if more work data sets are defined, they are used with only the primary allocation.
DFSORT uses only the space on the first volume specified for a multivolume data set. Space on the second and subsequent volumes is not used. Multivolume SORTWKdd data sets are, therefore, treated as single-volume SORTWKdd data sets.
DFSORT work data sets can exceed 65536 tracks if allocated as large format data sets on disk devices. Dynamically allocated disk work data sets are automatically allocated by DFSORT as large format. DSNTYPE=LARGE must be specified on SORTWKdd DD statements to allocate JCL work data sets as large format.
If primary space is fragmented, all but the first fragment are handled as secondary space.