System Global Area

In the database management systems developed by the Oracle Corporation, the System Global Area (SGA) forms the part of the system memory (RAM) shared by all the processes belonging to a single Oracle database instance. The SGA contains all information necessary for the instance operation.

In general, the SGA consists of the following:

From Oracle Database version 10g, Automatic Memory Management (AMM) allows simplified and dynamic configuration of the SGA.

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