NEC ExpressA1160 - Manual (Page 168)

Setting Performance Thresholds using ESMPRO Manager
9-6
indicator must move to return from a critical state to a warning and then to a normal
operating state.
Figure 9-2 shows the threshold and reset values for CPU load, which
has upper limits but no lower limits.
Figure 9-2 CPU Load Threshold and Reset Values
Reset values are offset from the thresholds to provide an operating buffer. When a
measurement hovers around a threshold, it can bounce over and under the threshold,
generating alerts each time it moves in and out of the warning or critical state. The range
between the threshold and reset values moderates the number of alerts generated. A
buffer of sufficient size eliminates the generation of unnecessary alerts if processing
activity hovers over and under the threshold. However, too large a buffer perpetuates
the error condition unnecessarily.
Example
For CPU load in Figure 9-2 , the threshold values are 60% and 79%. When processing
activity exceeds 60%, a warning is generated and the icon color changes to yellow. If the
activity exceeds 79%, a critical error is generated and the icon color changes to red.
The critical error continues until the measurement falls below the fatal (major) reset
value of 65%. At this time, a recovery message appears in the AlertViewer, and the
icons change from red to yellow. The buffer between 79% and 65% increases the
likelihood that the spike in processing has subsided and the error condition no longer
exists. The warning continues until the measurement falls below the warning (minor)
reset value of 53%. At this time, processing activity is considered normal, a recovery
message appears in the AlertViewer, and the icons change from yellow to green.