Tandem Capacity Model (TCM) Manual

1. Open a Performance model.
2. Select Consumption model. The Consumption model appears.
Actual data based on the workload-apportioned Measure data appears in the Actual column.
Default constraints appear in the Constraint column. The configuration recommended by TCM
appears in the Plan column.
3. Enter constraints in the input fields in the Constraint column and other selected cells. Then
press Return.
4. After entering all the changes you want in the input fields, press Return and then select Options
> Calculate Now (F12). If you select Calculate Now before pressing Return, TCM displays the
Save As dialog box for you to save the new model.
TCM calculates all the values in the Plan column to support the given constraints.
For more information, see “Using the Consumption Model” (page 90).
Using the Process Category Audit (PCAT) Report
You can use the Process Category Audit report to check the accuracy of the control file in
aggregating processes and discopen activity to process categories. If the aggregation does not
seem reasonable based on the report, review the PCAT statements in the control file and revise
the file if needed.
The report lists the processes aggregated into each process category as defined by the MeasTCM
control file. For each process, the report shows the number of CPU busy seconds and the number
of seconds the process was in the time boundaries set by the MeasTCM control file. In addition,
the report calculates the total CPU busy seconds for each process category.
Figure 13 (page 66) shows an excerpt of a sample Process Category Audit report. For more
information, see “Using the Process Category Audit Report” (page 62).
Using the Planning Timeline Model
The TCM Planning Timeline model is used to examine host response times and throughputs over
eight user-specified planning periods. Several growth scenarios can be specified, including:
• Throughput growth rate for OLTP transactions (Rate column) starts from the second column.
The first column is the Actual for the Basic Sample Data for the Consumption model. The First
Plan Scenario (second column) can be either the Actual Sample Data of the Consumption
Model or the Plan Data of the Consumption Model, depending on the button at the top right
corner of the Planning Timeline screen.
• Number of transactions per tasks growth rate for batch transactions (Rate column)
• Number of CPUs and/or disks over time
• CPU and disk type
You can display the results of the Planning Timeline model in a chart and print the chart. Default
behavior from the Planning Timeline line propagates to the right from column 2. You can define
behavior changes.
To use the Planning Timeline model:
1. Open a Performance model.
2. Select Find > Planning Timeline. The Planning Timeline model appears. Figure 26 (page 94)
shows a sample Planning Timeline model.
3. After entering all of the changes in the selected input fields, press Return and then select
Options > Calculate Now. You must press Return before selecting Calculate Now. TCM
calculates the values to reflect the changes.
For more information, see “Using the Planning Timeline Model” (page 91).
Using the Process Category Audit (PCAT) Report 251