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oracle 19c on Linux 8: Increase per process memlock (soft) limit to lock 100% SGA

seanzhFeb 24 2025 — edited Feb 24 2025

Hi, Oracle DB is 19.25 on Oracle Linux 8,

I have resource limits set like the screenshot here and yet I always see this warning during DB startup, I even duplicated these resource numbers to /etc/security/limits.conf but nothing can make these warnings go away, please advice, thank you very much in advance

Starting ORACLE instance (normal) (OS id: 2400)

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************************************************************

Instance SGA_TARGET = 8192 MB and SGA_MAX_SIZE = 9216 MB

************************************************************

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****************************************************

Sys-V shared memory will be used for creating SGA

****************************************************

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**********************************************************************

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Dump of system resources acquired for SHARED GLOBAL AREA (SGA)

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Per process system memlock (soft) limit = 64K

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Expected per process system memlock (soft) limit to lock

instance MAX SHARED GLOBAL AREA (SGA) into memory: 9218M

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Available system pagesizes:

4K, 2048K

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Supported system pagesize(s):

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PAGESIZE AVAILABLE_PAGES EXPECTED_PAGES ALLOCATED_PAGES ERROR(s)

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    4K       Configured              22        On-Demand        NONE

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 2048K                0            4609        On-Demand        NONE

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RECOMMENDATION:

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  1. For optimal performance, configure system with expected number

of pages for every supported system pagesize prior to the next

instance restart operation.

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  1. Increase per process memlock (soft) limit to at least 9218MB

to lock 100% of SHARED GLOBAL AREA (SGA) pages into physical memory

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**********************************************************************

Screenshot 2025-02-24 at 2.59.51 PM.png

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Added on Feb 24 2025
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