TurboIMAGE scalability II
- Lock dependency semaphores (one for each dataset) one at a time
- lock all the necessary data blocks
- release the dependency semaphore
- Release all the data block locks at end of intrinsic
- EHWM introduced for detail dataset
- EHWM resides in dataset user label, starts from 15th double word (1 base)
- each EHWM has 21 entries, each entry represents a block, with the 1st entry as a header
- each entry occupies 8 bytes
- allocated when the first DBPUT (if EHWM enabled) access the dataset
- deallocate when user disable EHWM
- DBUTIL >>ENABLE basename FOR EHWM