When an identity change occurs, the new identity might or might not have an OMVS segment associated with it. If an identity change takes place, the following happens:

1. If the new identity has the limit defined by RACF®, that limit overrides any other system control including the IEFUSI installation exit and the parent's inheritance structure.
2. If there is no RACF segment for the new identity, the IEFUSI installation exit might override the inheritance structure and set the limit.
3. If a RACF limit was not set for the new identity and if IEFUSI did not set the limit, the Inhe inheritance overrides the current values of the parent's inheritance structure.
4. The setting of the MAXASSIZE parameter in BPXPRMxx is the default for a new z/OS® UNIX identity if none of the other values applied (except for MEMLIMIT, which is set in SMFPRMxx).