(MVS/System Extensions), next to MVS/SP (MVS/System Product) Version 1, next to MVS/XA (MVS/eXtended Architecture), next to MVS/ESA (MVS/Enterprise Systems Architecture)
Machine/Extended Architecture Migration Aid VM/XA MA is intended to ease the migration from MVS/370 to MVS/XA by allowing both to run concurrently on the
2 GiB (231 bytes). In z/OS, the storage layout is similar to that of MVS/XA, MVS/ESA and OS/390; storage above the 2 GiB bar is managed by different services
MVS/System Product Version 3 (MVS/ESA), it also announced MVS/Data Facility Product Version 3 (MVS/DFP), 5665-XA3; MVS/SP V3 required either MVS/XA Data