Programming Systems Support - IBM System/370 Manual

SECTION 30: PROGRAMMING SYSTEMS SUPPORT
30:05 TRENDS IN DATA PROCESSING AND
PROG~NG
SYSTEMS
The Model 165 and its programming systems support have been designed
to operate in the data processing environment that has been emerging
since introduction of System/360.
52
Significant trends are the following:
• Growt~ toward more multiprogramming to improve system throughput.
Multiprogramming also permits the user to install new applications,
such as small teleprocessing inquiry, graphics, or time-sharing
applications, that would not otherwise justify a dedicated system.
Multiprogramming support also has encouraged the growth of new
computer environments, as indicated
by
the items that follow.
• Growth of integrated emulation, that is, concurrent native and
emulation mode processing on one system. The execution of emulators
under operating system control improves system throughput because
emulators can use control program facilities (stacked job execution,
data management functions, etc.) and because native mode and
emulator jobs can be scheduled to operate concurrently to utilize
available system resources efficiently. The use of integrated
emulators eliminates most reprogramming and eases transition from
one system to another, permitting the user to expend his efforts
extending and adding applications.
• Greater use of high-level languages, such as COBOL, FORTRAN, and
PL/I, for applications programming. The cost of programming has
been increasing while the cost of computing hardware has been
decreasing. More productive use of programmers can be achieved
by the use of high-level languages. Improvements to compile times
and to the size and execution speed of code produced by high-level
language translators have been made and continue to be made. The
support of many more functions within high-level languages also
has increased their use, and the growth of interactive computing
has stimulated the addition of even more facilities.
• Growth of teleprocessing applications such as remote inqUiry,
message switching, data collection, and management information
systems. The ability of System/360 and System/370 to handle
teleprocessing and batch processing in one system eliminates the
necessity of dedicated special purpose systems.
• Growth of remote computing activities, such as remote job entry
and interactive computing (or time-sharing) in both a nondedicated
and dedicated €nviro~~ent. Remote computing offers (1) fast
turnaround for batch work submitted from remote locations, (2)
remote user access to the large computing facilities and data base
available at the central installation, and (3) interactive problem
solving on a regular or a nonscheduled basis for personnel in
locations remote from the central computer. In-house interactive
computing is growing also as users attempt to use programmer time
more efficiently.
• Growth toward large, online data base systems. The growth in the
marketplace of remote computing, time sharing, and real-time
applications necessitates the instant availability of more and
more data. High-capacity, fast, reliable direct access devices
are required for this type of computing environment.