When DFSMSdss restores direct data sets, several processing options can be used. Direct data sets can be organized by relative block address or by track-track record (TTR).

Relative block addressable direct access data sets can be processed block by block to like and unlike target devices if the block size fits on the target track. When the data sets are processed block by block, DFSMSdss updates the block reference count of dummy records contained in the relative block addressed direct access data sets. To process block by block, the direct access data sets must have neither a variable record format nor a standard user label.

TTR direct access data sets may become unusable if they are processed block by block. TTR and relative block addressable data sets can be processed track by track to like and unlike target devices whose track capacity is equal to or greater than the source. Block by block processing is more efficient because track by track processing to an unlike device of larger track capacity can leave some unused space on each track of the target data set.