Changing DFSMShsm backup and migration generated dataset names to reduce contention for similar names and eliminating a possible performance degradation

In environments where many small similarly named datasets are backed up or migrated across multiple tasks and multiple instances of DFSMShsm, a possible contention for the target dataset name may occur. This contention could cause a performance degradation. DFSMShsm normally creates unique dataset names for its backup and migrate datasets using the form:

prefix.function.Tssmmhh.user1.user2.Xyddd

where prefix is the backup or migration defined prefix, function is either BACK or HMIG, Tssmmhh is a timestamp, user1 and user2 are the first two high-level qualifiers of the source dataset name, and Xyddd is a date.

After enablement of the feature, generated names will have Tssmmhh replaced with Tcccchh, where cccc is the time in hundredths of seconds from the beginning of the hour, converted to four alphabetic characters and hh is the hour.

See z/OS DFSMShsm Storage Administration. for more details and conversion information.

To activate the feature, issue the following:

PATCH .MCVT.+24C BITS(.......1)

To deactivate the feature, issue the following:

PATCH .MCVT.+24C BITS(.......0)