Oracle Cursor Usage Test

This test monitors the number of open cursors for a database instance. This test is disabled by default. To enable the test, go to the enable / disable tests page using the menu sequence : Agents -> Tests -> Enable/Disable, pick Oracle Database as the Component type, Performance as the Test type, choose this test from the disabled tests list, and click on the << button to move the test to the ENABLED TESTS list. Finally, click the Update button.

Target of the test : An Oracle server

Agent deploying the test : An internal agent

Outputs of the test : One set of results for every SID monitored.

Configurable parameters for the test
Parameter Description

Test period

How often should the test be executed

Host

The host for which the test is to be configured.

Port

The port on which the server is listening.

ORASID

The variable name of the oracle instance.

Username

In order to monitor an Oracle database server, a special database user account has to be created in every Oracle database instance that requires monitoring. A Click here hyperlink is available in the test configuration page, using which a new oracle database user can be created. Alternatively, you can manually create the special database user. When doing so, ensure that this user is vested with the select_catalog_role and create session privileges.

The sample script we recommend for user creation (in Oracle database server versions before 12c) for eG monitoring is:

create user oraeg identified by oraeg

create role oratest;

grant create session to oratest;

grant select_catalog_role to oratest;

grant oratest to oraeg;

The sample script we recommend for user creation (in Oracle database server 12c) for eG monitoring is:

alter session set container=<Oracle_service_name>;

create user <user_name>identified by <user_password> container=current default tablespace <name_of_default_tablespace> temporary tablespace <name_of_temporary_tablespace>;

Grant create session to <user_name>;                                

Grant select_catalog_role to <user_name>;

The name of this user has to be specified here.

Password

Specify the password of the specified database user.

Confirm Password

Confirm the Password by retyping it here.

Cursor Type

By default, this parameter is set to 'none' indicating that this test will report the "Current open cursors" measure based on the number of cursors that are open for all cursor types on the target database instance. However, if you want this test to report the number of cursors that are open for only a few cursor types of your interest, then, you can specify a comma-separated list of cursor types in this text box. For instance, this can be: OPEN, SESSION CURSOR CACHED.

IsPassive

If the value chosen is Yes, then the Oracle server under consideration is a passive server in an Oracle cluster. No alerts will be generated if the server is not running. Measures will be reported as “Not applicable" by the agent if the server is not up.

Measurements made by the test
Measurement Description Measurement Unit Interpretation

Current open cursors

The number of cursors currently opened by applications using the database

Number

Many open cursors can exist if any application does not properly close the ResultSets before closing a connection. Alternatively, many simultaneous queries to the database can also result in many open cursors. A continuous increase in open cursors is an indicator of a problem in an application’s use of the database.

Percent open cursors

This metric reports the average percentage of open cursors with respect to the total allowed limit.

Percent

If the percentage of open cursors nears 100%, then this could invoke the “maximum open cursors exceeded” error message. If the percentage is consistently near 100%, consider increasing the value of the ‘open_cursors’ parameter in the init file.