Oracle Database - System Global Area - SGA (Shared Memory)

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About

The SGA (System Global Area) is an area of memory allocated when an Oracle Instance starts up.

The SGA memory is shared by all sessions connected to Oracle Instance. See Virtual Memory - Shared Memory (SHM)

A group of shared memory structures that contain data and control information for an Oracle instance.

Oracle Database Sga

where:

Configuration

The SGA's size and function are controlled by initialization (INIT.ORA or SPFILE) parameters.




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