Siemens SM2 monitoring system User Manual

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U3585-J-Z125-8-76

SM2 reports

The PRIOR task scheduler uses three criteria for controlling main memory and CPU
utilization by the tasks. These criteria are

–

the task category,

–

the multiprogramming level, and

–

the task priority.

Detailed information on these criteria can be found in the manuals "Introductory Guide to
Systems Support" [6] and “Performance Handbook” [5]. In the following, only information
that is relevant for the SM2 reports is discussed.

In BS2000, 16 task categories are distinguished at present, i.e. the 4 standard categories

–

SYS (internal tasks and remote batch processing)

–

DIALOG (interactive mode)

–

BATCH (batch mode)

–

TP (inquiry-and-transaction mode)

and up to 12 categories that can be defined freely by the system administrator.

The multiprogramming level denotes the number of tasks of a given category that may use
main memory concurrently, i.e. the number of active tasks of a category.

In the /MODIFY-TASK-CATEGORIES command the system administrator uses the
category attributes

MIN MPL
MAX MPL
WEIGHT

to specify the relative priority of each category in order to make decisions regarding
activation (= allocation of authorization to use main memory).

MIN MPL is used to specify a minimum number of active tasks of a category. The system
tries to reach the specified MIN MPL value first.

MAX MPL is used when there is no fixed limit, i.e. activation continues even after the
maximum MPL value as long as no resource bottleneck occurs.

WEIGHT is used to control the sequence of activation.