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SGA_MAX_SIZE/MEMORY_MAX_TARGET Preallocated In On AIX (Doc ID 2329122.1)

Last updated on AUGUST 04, 2018

Applies to:

Oracle Database - Enterprise Edition - Version and later
Information in this document applies to any platform.


On AIX 7.1 platform, after upgrading from Oracle to Oracle noticed database uses much more Memory than before, right after startup.

It is noticed memory reserved/used for SGA is larger than SGA_TARGET. Specifically it is observed that up to SGA_MAX_SIZE is actually allocated out from the OS.

Testcase to illustrate the same:



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