Time distribution of activity level report
The Time Distribution of Activity Level report displays a chronological record of the activity level of the program or subsystem and of its primary file access activities. This report can help you determine the highest users of CPU time, particularly among storage devices.
TASK OR DDNAME
The first entries under TASK OR DDNAME (data definition name) describe task activity within the address space. Subsequent entries describe file access activities. The report lists the activities within each task or ddname in order of decreasing solo activity.
The report limits the number of task entries to six and the number of file access activities to eleven. It defines the top five tasks and groups the rest in OTHER. Also, if the program or subsystem has more than eleven active files, it groups the least active in an entry labeled OTHER. If you specify the ALLTASK parameter, the report will show all the tasks. Similarly, if you specify the ALLDD parameter, the report will list all the tasks or ddnames in which Strobe detected activity.
The report identifies tasks by the name of the module in which execution was initiated or by the name specified in the invocation of an ATTACH macro. When more than one task executes the same load module, Strobe prints the module name and a unique identifying number that corresponds to a task control block (TCB) address. For example, at the first occurrence of a load module that is executed in multiple tasks, Strobe prints the module name: LOADMOD 1, with the 1 being the unique identifying number. At the second occurrence of the same load module, Strobe prints: LOADMOD 2. At the third occurrence of the same load module, Strobe prints: LOADMOD 3. The unique identifier differentiates the instances that the load module occurs. If the load module executes only once, Strobe does not associate a number with the load module’s name.
If you specified the NOTASK reporting option, this report contains a single line showing the combined time distribution of all tasks.
The separate entry labeled .FILEMGT combines file access operations (such as open and close activities) or other file access activities performed by IOS drivers that Strobe could not assign to a specific file. If their collective activity is low compared to the accompanying tasks (the report limits the number of task entries to six), the report may include the file access operations in the .OTHER line entry instead.
RESOURCE
Resources in this column are listed for the following activities:
For file access activities, the model number of the I/O device that serviced each task appears. If the model is not available, the following device types appear:
C
Communication
DA
Direct access
G
Graphic
MT
Magnetic tape
UR
Unit record
- For CPU activities, the literal CPU appears.
- For activity in I/O services routines, the literal I/O appears.
- For files processed by the BatchPipes subsystem, the literal B_PIPES appears.
Time distribution chart
The time distribution section charts the distribution of processing activity on a horizontal scale with 100 graduations. Each vertical segment represents 1% of the measurement session. Consequently, any point on the chart corresponds to the execution of a task or file access activity during a particular one-hundredth of the measurement session, expressed as a proportion of all activity during that segment. Strobe rounds the values and represents them as follows:
- An asterisk (*) indicates activity greater than 95%.
- A single-digit entry indicates the activity percentage in tens.
- A dash (-) indicates activity less than 5% but greater than zero.
- A blank indicates no activity.
Because file access activities and task execution activities can overlap one another, the percentages in any column can amount to more than 100, depending on the extent of overlap.