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Hugepages are Not used by Database Buffer Cache (Doc ID 829850.1)

Last updated on FEBRUARY 20, 2019

Applies to:

Oracle Database - Enterprise Edition - Version 11.1.0.7 and later
Oracle Database Cloud Schema Service - Version N/A and later
Oracle Database Exadata Cloud Machine - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Oracle Database Cloud Exadata Service - Version N/A and later
Linux x86
***Checked for relevance on 27-Apr-2012***

Symptoms

Following the steps in <Note 748637.1> you have configured your Linux for Very Large Memory with HugePages.
As described on <Note 749851.1> you have MEMORY_TARGET & MEMORY_MAX_TARGET initialization parameters disabled as the use of 11g Automatic Memory Management (AMM) is incompatible with HugePages.
Your SGA size is less then the size of the HugePages_Total (HugePages_Total*Hugepagesize)
But despite this the HugePages are not used by the database buffer cache.


Here I would like to show you an example of a possible scenario:

Suppose to have a RDBMS instance ASM enabled:

Changes

 

Cause

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In this Document
Symptoms
Changes
Cause
Solution
References

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