When DFSMShsm does backup and recovery processing for extended
format SAM and VSAM compressed data sets, be aware of the following
results:
- When DFSMShsm backs up an extended format VSAM compressed data
set, it recovers that data set only as an extended format compressed
data set.
- When DFSMShsm backs up an extended format SAM compressed data
set, it recovers that data set as either an extended format compressed
or nonextended format SAM data set.
- When DFSMShsm backs up a compressed SAM or VSAM data set, it suspends
software compression for that data set.
- When a compressed SAM or VSAM data set is backed up, DFSMShsm
records in the BCDS that it is a compressed data set. It also records
both the compressed size of the data set and the size the data set
would be if it were not compressed. This information is passed to
DCOLLECT.