NEC Storage Performance Monitor/Optimizer User Manual page 135

Appendix A Commands of Performance Monitoring/Optimization Function
The value is provided as the average response time after summarizing.
More specifically, in each interval of the input file, the product of each interval time and each
average response time is calculated. The products are summed within the period of summarizing,
and the total response time in the period of summarizing is calculated. The average response time
of the period of summarizing is calculated by dividing the total response time in the period of
summarizing by the interval time after summarizing.
Average Transfer Rate
For statistic information items regarding average transfer rate, the average transfer rate in each
interval of the input file is converted to the average transfer rate of the period of summarizing. The
value is provided as the average transfer rate after summarizing.
More specifically, in each interval of the input file, the product of each interval time and each
average transfer rate is calculated. The products are summed within the period of summarizing,
and the total amount of transfer in the period of summarizing is calculated. The average transfer
rate of the period of summarizing is calculated by dividing the total amount of transfer in the period
of summarizing by the interval time after summarizing.
Maximum Response Time
For statistic information items regarding maximum response time, the maximum response time in
the period of summarizing is selected from the maximum response times in the intervals of the input
file. The value is provided as the maximum response time after summarizing.
Average Busy Ratio
For statistic information items regarding an average busy ratio, the average busy ratio in each
interval of the input file is converted to the average busy ratio of the period of summarizing. The
value is provided as the average busy ratio after summarizing.
Average Operating Time
For statistic information items regarding (average) operating time, the (average) operating time in
each interval of the input file is accumulated in the period of summarizing. The cumulative value
is provided as the (average) operating time after summarizing.
Additional information
When statistic information is summarized, if it is summarized into one value, information regarding
time changes in each logging Interval is lost. iSMprfarc add additional information of statistic
information to the summarized file. For I/O count, the maximum and minimum values of time
density of I/O count in each logging Interval are added. For average transfer rate, the maximum
and minimum values of average busy ratio in each logging Interval are added. For average
response time and maximum response time, no additional information is added because maximum
and minimum values are useless.
Maximum and Minimum Values of Time Density of I/O Count
The maximum and minimum values of time density of I/O count in each logging Interval in the
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