Oracle Exam 1Z0-060 Topic 8 Question 1 Discussion

The large pool can provide large memory allocations for the following:

/ (B)UGA (User Global Area) for the shared server and the Oracle XA interface (used where transactions interact with multiple databases)

/Message buffers used in the parallel execution of statements

/ (A) Buffers for Recovery Manager (RMAN) I/O slaves

Note:

* large pool

Optional area in the SGA that provides large memory allocations for backup and restore operations, I/O server processes, and session memory for the shared server and Oracle XA.

* Oracle XA

An external interface that allows global transactions to be coordinated by a transaction manager other than Oracle Database.

* UGA

User global area. Session memory that stores session variables, such as logon information, and can also contain the OLAP pool.

* Configuring the Large Pool

Unlike the shared pool, the large pool does not have an LRU list (not D). Oracle Database does not attempt to age objects out of the large pool. Consider configuring a large pool if the database instance uses any of the following Oracle Database features:

* Shared server

In a shared server architecture, the session memory for each client process is included in the shared pool.

* Parallel query

Parallel query uses shared pool memory to cache parallel execution message buffers.

* Recovery Manager

Recovery Manager (RMAN) uses the shared pool to cache I/O buffers during backup and restore operations. For I/O server processes, backup, and restore operations, Oracle Database allocates buffers that are a few hundred kilobytes in size.