Size eligibility for data sets to migrate to an SDSP

Data sets that meet certain size requirements can be migrated to SDSP data sets. Data set size is determined as follows:

Physical sequential data sets—by the high-used track, which is stored in the data set VTOC entry
Physical sequential data sets with zero secondary allocation—by allocated size
Partitioned data sets (not PDSE)—by the high-used track, which can include unused space within the data set
Partitioned data sets can only migrate to SDSPs when the following two conditions are met: (1) the migration request is for a volume (not for a data set) and (2) an AX cell exists in the catalog for the PDS. In these cases, eligible PDSs are migrated to SDSPs using DFSMSdss as the data mover.
Direct access data sets—by allocated size
VSAM data sets—by allocated size address (RBA)
PDSE data sets—by the high-used page, which is obtained from DFSMSdfp
HFS data sets—by the high-used page, which is obtained from DFSMSdfp
Unmounted zFS data sets—by allocated size address (RBA)

A candidate data set is eligible for migration to an SDSP data set if its estimated size is less than or equal to the number of KB or 3380 tracks that you specify with the SMALLDATASETPACKING parameter of the SETSYS command. (See Specifying small data set packing for an explanation of small data set packing.) A data set’s source size in KB in DFSMShsm is calculated as the number of bytes per track for the device type times the number of tracks used by the data set. For each device type in DFSMShsm the number of bytes per track is as follows:

Device Type	Bytes per Track
3380	47,476
3390	56,664

Note: If you specify the size eligibility in tracks, DFSMShsm converts the tracks value to KB with an assumed track size of a 3380 device type.