数据库大页配置遇到的问题

今天在配置数据库大页的时候，遇到一个问题，配置完成后 HugePages_Free 还有很多，和HugePages_Total竟然差不多，后面才研究了很久才发现是pre_page_sga参数为false导致，以下是数据库的alert日志

cat /proc/meminfo
HugePages_Total: 128020
HugePages_Free: 109396 <<<
HugePages_Rsvd: 109377
HugePages_Surp: 0
Hugepagesize: 2048 kB

–数据库alert
Starting ORACLE instance (normal)
************************ Large Pages Information *******************
Parameter use_large_pages = ONLY
Per process system memlock (soft) limit = UNLIMITED

Total Shared Global Region in Large Pages = 250 GB (100%)

Large Pages used by this instance: 128001 (250 GB) <<<<
Large Pages unused system wide = 19 (38 MB)
Large Pages configured system wide = 128020 (250 GB)
Large Page size = 2048 KB