System Monitor Guide and Reference

How to Read the Data Element Tables

The section for each data element begins with a table that lists standard information. An example is shown in Figure 3, followed by an explanation of each part of the table.

Figure 3. Sample Element Table

1. The level of information that can be captured by the snapshot monitor.
2. The data group where captured snapshot information is returned. If parsing the data stream directly, the element name is uppercased and prefixed with SQLM_ELM_.
3. The snapshot monitor switch that must be set to obtain this information.
4. Whether or not the counter can be reset (snapshot monitor only).
5. The event monitor must be created with this event type to collect this information. See Element Types.
6. The data group in which captured event information is returned. If parsing the data stream directly, the element name is uppercased and prefixed with SQLM_ELM_.
7. The name and type of element, as returned in the data group. If parsing the data stream directly, the element name is uppercased and prefixed with SQLM_ELM_.
8. References to related data elements or monitoring concepts.

This table is followed by a description of the element and information on how you can use it when monitoring your database.

Element Types

Data elements are classified by the following categories:

• Counter

  A counter counts the number of times an activity occurs. Counter values increase during monitoring. Most are resettable.

• Gauge

  A gauge indicates the current value for an item. This value can go up and down depending on database activity (for example, the number of locks held).

• Water mark

  A water mark indicates the highest (maximum) or lowest (minimum) value an element reached since monitoring was started. These are not resettable.

• Information

  An information element provides reference-type details of your monitoring activities. This can include items such as node names, aliases, and path details.

• Timestamp

  A timestamp indicates the date and time that an activity took place, by providing the number of seconds and microseconds that have elapsed since January 1, 1970. In the C language, for example, this can be converted to calendar date and time using the ctime() function.

• Time

  Time returns the number of seconds and microseconds spent on an activity.

Note:

Global monitoring aggregates snapshot data, see Taking a Global Snapshot for more details.