Open/Close/End of Volume enhancements for z/OS V2R2
Open/Close/End of Volume provides the following enhancements:
DEVSUPxx enhancements: In previous
releases, a subset of DEVSUPxx keywords were reset to their
default values whenever a member was processed, unless the values
were explicitly set in the member. Starting in V2R2, the current values
of all keywords are preserved when a DEVSUPxx member is processed,
unless the member explicitly specifies new values.In addition, beginning in V2R2, multiple DEVSUPxx members can be specified on a single SET DEVSUP command invocation, by specifying their two-digit member suffixes separated by commas.
- Dynamic exits for Open/Close/End of Volume:
This enhancement provides dynamic versions of the following Open/Close/End
of Volume tape installation exits, which can be changed and put into
effect without an IPL. In previous releases, these exits required
an IPL for changes to go into effect.
- Volume mount -- dynamic version is OCE_VOLUMEMOUNT
- File start – dynamic version is OCE_FILESTART
- File validate – dynamic version is OCE_FILEVALIDATE
- File end – dynamic version is OCE_FILEEND
- Label anomaly – dynamic version is OCE_LABELANOMALY.
- Controlling synchronization of files written to
tape: the new NUMFILES keyword on the SYNC parameter of the DCBE
macro provides for potential performance improvements and improved
recovery by letting you specify how many files should be written to
tape volumes by a given job, before a synchronization occurs. For
more information, see the DCBE section of DFSMS Macro Instructions
for Data Sets