Db Data Area Stats Test

All data volumes in a database instance are known collectively as the data area. The data area contains, amongst other things, the application data, the database catalog and the undo log entries of the database instance. This test monitors the usage of the data area.

Target of the test : A MaxDB server

Agent deploying the test : An internal agent

Outputs of the test : One set of results for the MaxDB server being monitored.

Configurable parameters for the test
Parameter Description

Test Period

How often should the test be executed.

Host

The host name of the server for which the test is to be configured.

Port

The port number to which the server is listening.

DatabaseName

The test connects to a database on MaxDB and extracts performance statistics from the system tables in the database. Therefore, provide the name of a database in the DatabaseName text box.

Username

Since users with the SYSDBA privilege alone are allowed access to system tables, specify the name of such a user against Username.

Password

Provide the Password that corresponds to the specified Username.

Confirm Password

Confirm the password by retyping it here.

Measurements made by the test
Measurement Description Measurement Unit Interpretation

Usable size

Indicates the data area that is currently available for data.

MB

There must also always be sufficient space in the data area to hold all the data that is created during database operations. Therefore, ideally, this value should be high.

Used size

Indicates the memory in data area that is currently used for data.

MB

 

Data area usage

Indicates the percentage of memory in the data area that is actually used for data.

Percent

Ideally, this value should not be very high.

Data on volume

Indicates the amount of data that has been written to the data area, currently.

MB

 

Data not on volume

Indicates the amount of permanent data that has to be written to the data area at the next savepoint.

MB

Pagers (which are tasks in the user kernel thread) write the data from the data cache to the data area for each savepoint. If a lot of data was changed and the pagers would have to write many pages at the next savepoint, then the pagers write data from the data cache to the data area before the next savepoint.

Permanent size used

Indicates the data area that is currently used for permanent data.

MB

 

Temporary size used

Indicates the data area that is currently used for temporary data.

MB

A large proportion of temporary data indicates large amounts of (buffer) result sets. If the value of this measure is high, then find the statement that is causing large amounts of (buffer) result sets to be created, and check the access strategies for this statement.