Virtual storage usage

CICS® regions that previously used local DL/I can obtain considerable virtual storage constraint relief because the following storage areas reside in the DBCTL address spaces: all DL/I and DBRC code and control blocks, OSAM and VSAM buffer pools and related control blocks, PSB, DMB, and ENQ pools.

However, DBCTL requires some MVS™ CSA storage, which can lower the maximum available region size in the MVS system. See System administration in IMS product documentation for details of CSA and other DBCTL storage requirements.