Siemens Network Hardware SM2 monitoring system ユーザーズマニュアル
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Notes on SM2 operation
Accuracy of the SM2 data
6.2 Accuracy of the SM2 data
This section indicates the major factors affecting the accuracy of the data supplied by SM2
or SM2R1. The accuracy of some particularly important variables is also discussed.
or SM2R1. The accuracy of some particularly important variables is also discussed.
Inaccuracies resulting from rounding problems are not considered here.
6.2.1
Causes of inaccuracies
Like all software monitors, SM2 runs under the system to be monitored and thus requires
certain resources for its own operation; therefore, strictly speaking, it modifies the system
to be monitored. However, this influence is small and can generally be disregarded. For a
description of system utilization, see section 7.1.
certain resources for its own operation; therefore, strictly speaking, it modifies the system
to be monitored. However, this influence is small and can generally be disregarded. For a
description of system utilization, see section 7.1.
Inaccuracies resulting from marginal problems
Ideally, the SM2 activities during monitoring activation and deactivation, during the taking
of samples and at the end of a monitoring cycle operand, should take no time at all. This
being impossible, certain inaccuracies result. However, this effect is minimal and decreases
in direct proportion to the number of actions that have to be performed at any given time
(small number of tasks, devices etc. to be monitored).
of samples and at the end of a monitoring cycle operand, should take no time at all. This
being impossible, certain inaccuracies result. However, this effect is minimal and decreases
in direct proportion to the number of actions that have to be performed at any given time
(small number of tasks, devices etc. to be monitored).
Inaccuracies resulting from classification
Some SM2 values are gathered on a system-global basis, on a category-specific basis,
and/or on a task-specific basis. For category-specific data, SM2 uses the category
assignment that is valid at the time the data is collected (sample or event). However, SM2
does not recognize category switches for the TASK monitoring program. This is why
comparisons between task data accumulated by category and category-specific SM2 data
may lead to interpretation errors.
and/or on a task-specific basis. For category-specific data, SM2 uses the category
assignment that is valid at the time the data is collected (sample or event). However, SM2
does not recognize category switches for the TASK monitoring program. This is why
comparisons between task data accumulated by category and category-specific SM2 data
may lead to interpretation errors.