2. PERFORMANCE REPORTING ANALYSIS › 2.2 Real Storage Management Analysis › 2.2.4 MVS Concepts

2.2.4 MVS Concepts

The methodology section is an introduction to the concepts
underlying Real Storage Management (RSM) and the control
mechanisms available within MVS that affect real storage.
Real storage management is the efficient allocation of the
system's real memory to each of the various active programs
in the system.

This section explains the concept of virtual storage as it
relates to MVS systems and Real Storage Management.  First,
as a foundation for these concepts, we present a very brief
history of the development of hardware addressing schemes
leading up to the current virtual systems.  Next, we describe
the layout of the virtual storage in MVS.  We then explain
the parts of the virtual memory that can be controlled or
tracked in terms of real storage management.  Finally, an
overview is provided of expanded storage and how this can be
managed.  We provide examples to illustrate these concepts.
The following sections include discussions of each of these
topics:

    1 - Virtual Storage Concepts
    2 - MVS Virtual Storage Overview
    3 - MVS Real Storage Control Mechanisms
    4 - Expanded Storage Concepts