Two bytes of the block masks define the status of one RACF® database block. Each bit corresponds to
a 256-byte slot within a block. If a bit is set to 1, the corresponding
slot is free. In Figure 1 , only the
first six slots are in use. Figure 1. Block
Masks of the Database
The BAM high-water mark contained in the ICB is the address of
the BAM block from which segments were last allocated or deallocated.
This BAM block is used first when starting a search for space for
a new allocation.
