How Metric Data is Gathered

Data for metrics is gathered differently depending on the metric change type, time scope, and gathering time associated with the metric.

For more information on how these apply to individual metrics, see System Metrics.

Metric Change Type

The value that is displayed for a metric depends on the change type, as shown in the following table.

Table 1. Metric change types
Change Type	Description
Counter	The value is a sum that increases with each change. For example, number of requests is a counter change type.
Gauge	The value may increase or decrease over time, depending on events. For example, the number of processes running at any time is a gauge change type.

The interval over which a metric value is gathered differs by metric, as shown in the following table.

Table 2. Metric time scopes
Time Scope	Description
Point in time	The value is gathered at a specific point in time, such as when you reset a metric group or restart a service
Since reset	The value is gathered over the interval since the last reset of the metric

The time at which a metric value is gathered differs by metric, as shown in the following table.

Table 3. Metric gathering times
Gathering Time	Description
On change	The value is collected when a change occurs, such as when the number of requests changes
On demand	The value is gathered when you select a new item in the Scorecard pane, or reset a metric group. For more information, see Panes on the Status System Page and Resetting metrics.
Unknown	The gathering time is unknown