The Device Activity report gives information on I/O device use for all online devices you requested either by device class, by device number, or by volume serial number.
The Device Activity report, like the Monitor I session report, can help you to analyze device performance, to identify bottlenecks caused by a particular device, and to overcome obstacles that prevent efficient use of the resource.
Requesting the report during a display session enables you, for example, to track the device use on a real-time basis. You can get a timely picture of device use or track a specific critical device on a real-time basis, thus making it possible to take corrective action immediately.
To evaluate the data, you need to understand what a reporting period is and how it relates to the Monitor I interval.
The I= field in the header of each report shows the percentage of the Monitor I interval that has elapsed when RMF generates the Monitor II session report.
# Samples Taken * Cycle Time
I = ----------------------------
Monitor I Interval LengthFor a report that reflects the total device activity (delta mode is off), the reporting period is the time that has elapsed from the start of the Monitor I interval to the time when you requested the report. The maximum reporting period is one Monitor I interval. When a Monitor II report covers a complete Monitor I interval, the I= field contains an upper-case 'T' (I=T).
The I= field in the header of the report equals the percentage of the interval that is represented by the data; thus, for your initial request, the I= field equals the percentage of the interval that expires between your initial request and the time you press the ENTER key. For all subsequent requests, the I= field equals the percentage of the interval that expires.