I have been trying to switch from oracle AMM to ASMM huge pages. I have done the following changes on RHEL 6
Added following entry in /etc/sysctl.conf ( as suggested by hugepages_setting.sh )
vm.nr_hugepages=777 Added following entry in /etc/security/limits.conf
oracle soft memlock 2831155 oracle hard memlock 2831155 rebooted the server changed oracle parameters memory_target, memory_max_target, sga_target, sga_max_target, use_large_pages to specific values.
After a database restart, I can see the following:
[root@rheloracle ~]# grep -i huge /proc/meminfo AnonHugePages: 0 kB HugePages_Total: 777 HugePages_Free: 8 HugePages_Rsvd: 0 HugePages_Surp: 0 Hugepagesize: 2048 kB And when I shutdown the database I could see the HugePages_Free is equal to HugePages_Total.
[root@rheloracle ~]# grep -i huge /proc/meminfo AnonHugePages: 0 kB HugePages_Total: 777 HugePages_Free: 777 HugePages_Rsvd: 0 HugePages_Surp: 0 Hugepagesize: 2048 kB Looks like HugePage configuration at db level and o/s level are in sync and in use. But all the examples and documents (i have referred) indicate that HugePages_Rsvd should have a non zero value after enabling huge pages. But same is not happening in my case. Can you please suggest if I am missing something or it's normal to have HugePages_Rsvd 0.
(I am running oracle 18c xpress edition on RHEL6)
