Create and Edit Calculators

Calculators take the values from a metric grouping as input, and average or sum the values.  The calculators output the resulting value as a custom metric in the Investigator tree. Calculator-generated metrics appear under a virtual process, named the Custom Metric Process. The custom metric process runs on a virtual host that is named the Custom Metric Host.
About Calculators
Calculators can average or sum the values from a metric grouping and then generate custom metrics in the Investigator tree. Calculator metrics that are run on a virtual process, named the custom metric process. This process runs on a virtual host, the custom metric host.
Supportability metrics gather data using calculators. To report data correctly, any MOM-based calculator requires data from at least one Collector. Without Collector data, the MOM cannot calculate and display metrics.
On a MOM, you want to view the metric
(.*)\|Custom Metric Process \(Virtual\)\|Custom Metric Agent \(Virtual\)Enterprise Manager\|Configuration:Number of Metric Groupings
. You expect a metric value greater than 0.
When the MOM has no Collector that is connected, the
Number of Metric Groupings
metric reports 0.
When the MOM has at least one Collector that is connected, the
Number of Metric Groupings
metric reports the correct value.
Management Module Calculator
The management module calculator performs simple calculations on metrics such as Sum, Average, Min, and Max.
Create a Calculator
You can create a calculator for a metric group.
Follow these steps:
  1. In Team Center, select
    The Calculators page displays a list of calculators which are grouped based on the Management Modules.
  2. Select
    Create Calculator
    The Create Calculator page appears.
  3. To edit a calculator, select the calculator that you want to update.
    The Edit Calculator:
    page appears.
  4. In the
    Management Module
    drop-down, select the desired module to be applied to the simple calculator that you create. You can also select
    Create Management Module
    to create a Management Module in a separate dialog.
  5. In the
    field, enter the required description that helps you identify the simple calculator that you create.
  6. In the
    Metric Grouping
    field, select the desired metric grouping to be applied to the simple calculator that you create. You can also select
    Create Metric Grouping
    to create a Metric Grouping in a separate dialog.
  • When the calculator is created, a metric grouping is automatically created with the same name as the calculator. However, the metric grouping must be customized before it can supply data to the calculator.
  • Select a metric grouping that provides integer values. Calculators cannot accept non-integer values as input. Mixed types produce unexpected results.
Calculators and Weighted Averages
Introscope calculators can produce metrics that are based on averages. The calculations are based on weighted averages, not straight averages. Weighted averages are useful when monitoring the performance of your application in a clustered environment. In this situation, you can see accurate response time between multiple servers that are likely to have different load levels.
You have a calculator generating a metric from the average response time for five servlets. A straight average would add up the response time for a defined time period, and divide by five. A weighted average would give more weight to the servlets that are called more often, giving a more accurate average.
Changing Operation Types in Management Module Calculators
When you edit a calculator in a management module, changing the operation type to redefine the meaning of calculator output metric. For example, from MIN to MAX. If you keep the calculator output metric name the same, viewing this metric juxtaposes the old values in history (calculated, for example, by the MIN) with the new values (for example, the MAX). Viewing the output metric gives no indication about where the alteration in processing occurred. If users can get confused, rename the calculator output metric of the calculator when you change the operation type.