Expert Oracle Database Architecture: Techniques and Solutions for High Performance and Productivity

© The Author(s), under exclusive license to APress Media, LLC, part of Springer Nature 2022

D. Kuhn, T. KyteExpert Oracle Database Architecturehttps://doi.org/10.1007/978-1-4842-7499-6_4

4. Memory Structures

Darl Kuhn¹   and Thomas Kyte²

(1)

Morrison, CO, USA

(2)

Denver, CO, USA

 

In this chapter, we’ll look at Oracle’s three major memory structures:

• System Global Area (SGA): This is a large, shared memory segment that virtually all Oracle processes will access at one point or another.

• Process (or Program) Global Area (PGA): This is memory that is private to a single process or thread; it is not accessible from other processes/threads.

• User Global Area (UGA): This is memory associated with your session. It is located either in the SGA or the PGA, depending ...