在RHEL6.7上开启大页内存

************************ Large Pages Information *******************
Per process system memlock (soft) limit &＃61; 64 KBTotal Shared Global Region in Large Pages &＃61; 0 KB (0%)Large Pages used by this instance: 0 (0 KB)
Large Pages unused system wide &＃61; 0 (0 KB)
Large Pages configured system wide &＃61; 0 (0 KB)
Large Page size &＃61; 2048 KBRECOMMENDATION:Total System Global Area size is 1506 MB. For optimal performance,prior to the next instance restart:1. Increase the number of unused large pages byat least 753 (page size 2048 KB, total size 1506 MB) system wide toget 100% of the System Global Area allocated with large pages2. Large pages are automatically locked into physical memory.Increase the per process memlock (soft) limit to at least 1514 MB to lock100% System Global Area&＃39;s large pages into physical memory
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根据如上信息,

在/etc/sysctl.conf中加入:

vm.nr_hugepages &＃61; 753

在:/etc/security/limits.conf中加入:

* soft memlock 1550336
* hard memlock 1550336注:1550336&＃61;1514MB*1024





重启os之后,startup 时的数据库实例日志如下:

************************ Large Pages Information *******************
Per process system memlock (soft) limit &＃61; 1514 MBTotal Shared Global Region in Large Pages &＃61; 1506 MB (100%)Large Pages used by this instance: 753 (1506 MB)
Large Pages unused system wide &＃61; 0 (0 KB)
Large Pages configured system wide &＃61; 753 (1506 MB)
Large Page size &＃61; 2048 KB
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