Tuning MVS

Experience contributes important knowledge in many procedures.
Front the experience gained in tuning the Multiple Virtual
Storage (MVS) operating system, a set of guidelines to help MVS
installations avoid performance problems are suggested, along
with an approach to tuning an MVS system. The guidelines can
help a performance analyst isolate the cause of a performance
problem. Not all possible problems that might be encountered
are included. It is found that mosMt VS performance problems are
a result of poor workload management and are often related to
IIO activities.
An MVS tuning approach
by R. M. Schardt
Effective tuning of the Multiple Virtual Storage (MVS) operating
system (the later releases of oS/vs2)1 requires knowledge of MVS
operations, knowledge of the particular system to be tuned, and
tuning experience. Earlier papers have dealt with different aspects
of MvS but this paper addresses the issue of experience
by sharing with the reader the MVS tuning experience of
IBM’S Washington Systems Center staff. Some knowledge of MVS
and its associated terminology is assumed.
In some respects this paper could be considered a primer for the
performance analyst who has been trained on MVS but may not
have had much “hands-on” experience. This information is also
useful to managers responsible for system performance. Included
are suggestions as to the kinds of activities that are needed to
manage performance in a data processing installation. The paper
addresses those situations thatte nd to be common or reoccurring
performance issues.
Included in this paper are “rules of thumb,” or guidelines, that
can be used to help pinpoint the cause of actual or potential performance
problems. The primary source for these guidelines is
the experience gained from studies and from solving actual performance
problems, and for that reason, the guidelines are subjec to
change with increasing experience. These guidelines
should be used along with knowledge of other system factors to
determine the probable source of a performance problem.
Copyright 1980 by International Business Machines Corporation. Copying is
permitted without payment of roydty provided that (1) each reproduction is done
without alteration and (2) the Journal reference and IBM copyright notice are
included on the first page. The title and abstract may be used without further
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to republish other excerpts should be obtained from the Editor.