Release : 12.1
When allocating multi volumes for the CA 7 Datacom datasets in hlq.CAL2JCL(AL2DCA30), the additional extents are allocated during the DBUTILITY INIT function.
For example, for a DD statement with VOL=SER=(VOL1,VOL2,VOL3) and the VOLUMES keyword is not used in the DBUTLTY:
the INIT function will initialize 1 to 16 extents in VOL1 space availability, 1 to 16 extents in VOL2 space availability and 1 more extent in VOL3. The unused extents will be used for dynamic extend.
Example: VOL=SER=(VOL1,VOL2,VOL3) with SPACE=(CYLS,(100,50))
VOL1 (100x1pri extent)+(50x15 sec extent) = 850 cyls = 16 extents
VOL2 50x16 sec extent = 800 cyls = 16 extents
VOL3 50x1 sec extent = 50 cyls = 1 extents
TOTAL = 1700 cyls = 33 extents
If the keyword VOLUMES= is specified with a number value that is less than the number of volumes provided, the INIT function only initializes the number specified in the VOLUMES= keyword. For example, for a DD statement with VOL=SER=(VOL001,VOL002,VOL003), without the VOLUMES= keyword DBUTLTY initializes 1 to 16 extents on VOL001, 1 to 16 extents on VOL002, and 1 (or more) extents on VOL003. But with the VOLUMES= keyword set as VOLUMES=2, DBUTLTY initializes 1 to 16 extents on VOL001 and one (or more) extents on VOL002. Unused extent possibilities on VOL002 and VOL003 are available for dynamic extend.