近期，在一个LINUX环境的数据库使用HugePages时，启动数据库实例时发现有一个告警信息
Starting ORACLE instance (normal)
************************ Large Pages Information *******************
Parameter use_large_pages = ONLY =====>>>>
Per process system memlock (soft) limit = UNLIMITED =====>>>>
Large page usage restricted to processor group "user.slice"
Total Shared Global Region in Large Pages = 240 GB (100%)
WARNING:
The parameter _linux_prepage_large_pages is explicitly disabled.
Oracle strongly recommends setting the _linux_prepage_large_pages
parameter since the instance is running in a Processor Group. If there is
insufficient large page memory, instance may encounter SIGBUS error
and may terminate abnormally.
Large Pages used by this instance: 122881 (240 GB)
Large Pages unused in Processor Group user.slice = 1119 (2238 MB)
Large Pages configured in Processor Group user.slice = 124000 (242 GB)
Large Page size = 2048 KB
当前参数来看，使用了参数use_large_pages = ONLY、配置process system memlock (soft) limit = UNLIMITED；这个告警信息，MOS文档WARNING : Parameter _linux_prepage_large_pages Is Explicitly Disabled (Doc ID 2414778.1)上有明确解释，The message is just a warning and is meant for informational purposes。 并有给出解决方案，设置一个隐含参数，重启数据库后不再出现此告警。
WARNING : Parameter _linux_prepage_large_pages Is Explicitly Disabled (Doc ID 2414778.1)
alter system set '_linux_prepage_large_pages'=TRUE scope=spfile;
重启后日志中不再出现：
Mon Jan 10 22:59:00 2022
Starting ORACLE instance (normal)
Mon Jan 10 23:00:06 2022
************************ Large Pages Information *******************
Parameter use_large_pages = ONLY
Per process system memlock (soft) limit = UNLIMITED
Total Shared Global Region in Large Pages = 240 GB (100%)
Large Pages used by this instance: 122881 (240 GB)
Large Pages unused system wide = 1119 (2238 MB)
Large Pages configured system wide = 124000 (242 GB)
Large Page size = 2048 KB
********************************************************************
LICENSE_MAX_SESSION = 0
关于use_large_pages及内存大页的信息，可以参考MOS文档：
WARNING : Parameter _linux_prepage_large_pages Is Explicitly Disabled (Doc ID 2414778.1)
HugePages on Linux: What It Is... and What It Is Not... (文档 ID 361323.1)
HugePages and Oracle Database 11g Automatic Memory Management (AMM) on Linux (文档 ID 749851.1)
HugePages on Oracle Linux 64-bit (文档 ID 361468.1)