Oracle的SGA

Oracle数据库的基本体系结构包括：physical and logical storage structures也就是物理和逻辑存储结构，物理存储结构即数据库，逻

Automatic Shared Memory Management

In previous database releases, a database administrator (DBA) was required to

manually specify different SGA component sizes by setting a number of initialization

parameters, including the SHARED_POOL_SIZE , DB_CACHE_SIZE , JAVA_POOL_

SIZE, and LARGE_POOL_SIZE parameters. Oracle Database 10g includes the

Automatic Shared Memory Management feature which simplifies the SGA memory

management significantly. In Oracle Database 10g, a DBA can simply specify the total

amount of SGA memory availabl e to an instance using the SGA_TARGET initialization

parameter and the Oracle Database will au tomatically distribute this memory among

various subcomponents to ensure mo st effective memory utilization.

When automatic SGA memory management is enabled, the sizes of the different SGA

components are flexible and can adapt to the needs of a workload without requiring

any additional configuration. The database automatically distributes the available

memory among the various components as required, allowing the system to maximize

the use of all available SGA memory.