<operating system> An operating system from IBM, released with the IBM S/370 and originally known as OS/MVT. OS/VS2 R1 was known as SVS (Single Virtual Storage) as it had a single 16 MB virtual address space. OS/VS2 R2 was known as MVS - Multiple Virtual Storage.
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Nearby terms: OSSL « OSTA « OS/VS1 « OS/VS2 » OT » OTDR » OT&E