NEC Storage Performance Monitor/Optimizer User Manual page 17

A threshold value is specifiable for each calculation unit displayed by the Real-Time Display function (refer to Table
1-1). The unit of specifying a threshold is called a threshold monitoring element. Thresholds can be specified by
clients with the user level (Note 1) L2 or L3.
(Note 1)
For user levels, refer to 5.2 "Client Start/Stop" of the "NEC Storage Manager User's Manual" of your OS.
(1) Notifying threshold excess by e-mail
You can also e-mail the message notifying you of occurrence of an exceeded threshold to a specified address by using
the link function of the iSM server. For details of the link function of the iSM server, refer to 3.6 "Event Link" in the
"NEC Storage Manager User's Manual" of your OS.
(2) Threshold monitoring conditions
During a background process of disk array, such as batch processing and fault recovery of physical disks, a threshold
value may be temporarily exceeded. Upon such a case, which can occur in usual operation in general, exceeding of
threshold should not be reported to an administrator. Specifying the monitoring conditions shown below can prevent
such unnecessary reporting of exceeded threshold.
1. Threshold monitoring interval
Time interval of judging threshold. Default value is the same as Display Refresh Interval.
2. Minimum I/O count
If the number of I/Os in a threshold monitoring interval does not exceed an I/O count specified here, the threshold
is not monitored in this interval. A minimum I/O count is specified with the number of I/Os per minute.
Default value is 60/minute.
A threshold is monitored if the number of I/Os in a threshold monitoring interval exceeds the minimum I/O count, and
if the threshold is exceeded, threshold exceeding is reported. By operating businesses, analyzing performances, and
specifying the threshold monitoring conditions on the basis of the analysis, monitoring of overload appropriate for the
businesses. Figure 1-6 shows an outline of the threshold monitoring interval.
Chapter 1 Overview of Performance Monitoring Function
Figure 1-5 Monitoring Overloads
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