Managing ILM ADO Parameters

You can customize your ADO environment with ILM ADO parameters described in Table 5-2.

Table 5-2 ILM ADO Parameters

Name Description


The ENABLED parameter controls ADO background evaluation and execution. The default is enabled on (TRUE or 1).

The settings of ENABLED and the HEAT_MAP initialization parameters interact as follows:

  • If the HEAT_MAP initialization parameter is set to ON and the ENABLED parameter is set to FALSE (0), then heat map statistics are collected, but ADO does not act on the statistics automatically.

  • If the HEAT_MAP initialization parameter is set to OFF and the ENABLED parameter is set to TRUE (1), then heat map statistics are not collected and because ADO cannot rely on the heat map statistics, ADO does nothing. ADO behaves as if ENABLED is set to FALSE.


The value for RETENTION TIME specifies the length of time that data of completed ADO tasks is kept before that data is purged. The default is 30 days.


The value for JOB LIMIT controls the maximum number of ADO jobs at any time. The maximum number of concurrent ADO jobs is calculated as (JOB LIMIT)*(number of instances)*(number of CPUs for each instance). The default is 10.


The value of EXECUTION MODE controls whether ADO executes in online or offline mode. The default is online.


The value of EXECUTION INTERVAL determines the frequency that ADO initiates background evaluation. The default is 15 minutes.


The value for TBS_PERCENT_USED parameter specifies the percentage of the tablespace quota when a tablespace is considered full. The default is 85 percent.


The value for TBS_PERCENT_FREE parameter specifies the targeted free percentage for the tablespace. The default is 25 percent.

For the values of the TBS_PERCENT* parameters, ADO makes a best effort, but not a guarantee. When the percentage of the tablespace quota reaches the value of TBS_PERCENT_USED, ADO begins to move data so that percent free of the tablespace quota approaches the value of TBS_PERCENT_FREE. As an example, assume that TBS_PERCENT_USED is set to 85 and TBS_PERCENT_FREE is set to 25, and that a tablespace becomes 90 percent full. ADO then initiates actions to move data so that the tablespace quota has at least 25 percent free, which can also be interpreted as less than 75 percent used of the tablespace quota.

You can display the parameters with the DBA_ILMPARAMETERS view. For example, the following query displays the values of the ADO-related parameters.


NAME                                                             VALUE
---------------------------------------------------------------- ----------
ENABLED                                                                   1
RETENTION TIME                                                           30
JOB LIMIT                                                                10
EXECUTION MODE                                                            3
EXECUTION INTERVAL                                                       15
TBS PERCENT USED                                                         85
TBS PERCENT FREE                                                         25

7 rows selected.

You can set ILM ADO parameters with the CUSTOMIZE_ILM procedure in the DBMS_ILM_ADMIN PL/SQL package, as shown in Example 5-8. For information about setting ILM ADO parameters with Oracle Enterprise Manager Cloud Control, refer to "Managing ILM Heat Map and ADO with Oracle Enterprise Manager".

See Also:

Oracle Database PL/SQL Packages and Types Reference for information about the constants in the DBMS_ILM_ADMIN package