Chapter 12. Managing Server Resources

Through built-in packages, Oracle is now exposing more information about database internals—information that is not directly visible in the catalog. This chapter describes two packages that expose useful information.


Gives DBAs an analysis of the amount of space both used and free within a table, index, or cluster segment. It also provides information about segment free list sizes—information of special interest to Oracle Parallel Server administrators.


On the memory side, gives DBAs some measure of control over the Oracle System Global Area’s (SGA’s) shared pool. By pinning large packages into the shared pool, expensive runtime memory management (and even errors) can be avoided.

DBMS_SPACE: Obtaining Space Information

The DBMS_SPACE package provides procedures for obtaining space utilization information about table, index, and cluster segments. This information is not directly available through the Oracle data dictionary views. It can be used to report on and track segment space consumption in an Oracle database more accurately than by monitoring extent allocation alone. By measuring segment growth rates over time, DBAs can better predict the need for additional space in the database.

Getting Started with DBMS_SPACE

The DBMS_SPACE package is created when the Oracle database is installed. The dbmsutil.sql script (found in the built-in packages source code directory, as described in Chapter 1) contains the source ...

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