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Oracle 12.1.0.2 memlock changes with RHEL 7 OS

user12263870Dec 14 2022

after upgrading from Oracle 11.2.0.2 to 12.1.0.2 in RHEL 7 environment. I noticed the following in the alert log:
+---------------------------------------------------------------------------------------------------+
Wed Nov 16 20:32:01 2022
Dump of system resources acquired for SHARED GLOBAL AREA (SGA)

Wed Nov 16 20:32:01 2022
Per process system memlock (soft) limit = 64K
Wed Nov 16 20:32:01 2022
Expected per process system memlock (soft) limit to lock
SHARED GLOBAL AREA (SGA) into memory: 5120M
Wed Nov 16 20:32:01 2022
Available system pagesizes:
4K, 2048K
Wed Nov 16 20:32:01 2022
Supported system pagesize(s):
Wed Nov 16 20:32:01 2022
PAGESIZE AVAILABLE_PAGES EXPECTED_PAGES ALLOCATED_PAGES ERROR(s)
Wed Nov 16 20:32:01 2022
4K Configured 1310727 1310727 NONE
Wed Nov 16 20:32:01 2022
Reason for not supporting certain system pagesizes:
Wed Nov 16 20:32:01 2022
2048K - Dynamic allocate and free memory regions
Wed Nov 16 20:32:01 2022
RECOMMENDATION:
Wed Nov 16 20:32:01 2022

  1. Increase per process memlock (soft) limit to at least 5120MB
    to lock 100% of SHARED GLOBAL AREA (SGA) pages into physical memory
    +---------------------------------------------------------------------------------------------------+
    I updated the file: /etc/security/limits.conf with:
    oracle soft memlock 6291456
    oracle hard memlock 6291456
    I also added the following to the file: /etc/systemd/system/dbora.service with:
    LimitMEMLOCK=infinity
    LimitNOFILE=65535
    +---------------------------------------------------------------------------------------------------+
    After making the linux changes, I bounced the Oracle database and I am now seeing this in the alert log:
    ----- After change -------
    Wed Dec 14 19:26:04 2022
    Dump of system resources acquired for SHARED GLOBAL AREA (SGA)
    Wed Dec 14 19:26:04 2022
    Per process system memlock (soft) limit = 128G
    Wed Dec 14 19:26:04 2022
    Expected per process system memlock (soft) limit to lock
    SHARED GLOBAL AREA (SGA) into memory: 5120M
    Wed Dec 14 19:26:04 2022
    Available system pagesizes:
    4K, 2048K
    Wed Dec 14 19:26:04 2022
    Supported system pagesize(s):
    Wed Dec 14 19:26:04 2022
    PAGESIZE AVAILABLE_PAGES EXPECTED_PAGES ALLOCATED_PAGES ERROR(s)
    Wed Dec 14 19:26:04 2022
    4K Configured 1310727 1310727 NONE
    Wed Dec 14 19:26:04 2022
    Reason for not supporting certain system pagesizes:
    Wed Dec 14 19:26:04 2022
    2048K - Dynamic allocate and free memory regions
    Wed Dec 14 19:26:04 2022
    +---------------------------------------------------------------------------------------------------+
    My question:
    based on the message in the alert log above, did my changes satisfy the original RECOMMENDATION? Do I need to make any other changes? I am not seeing a "RECOMMENDATION" message after the change so I am assuming the changes to the linux OS for memlock completed the RECOMMENDATION changes.
    Thank you for your time and help.
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Added on Dec 14 2022
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