Verify that the soft and hard values in kilobytes of memlock that are configured in /etc/security/limits.conf are slightly smaller than the amount of installed memory. For example, if the system has 64GB of RAM, the values shown here would be appropriate:

soft memlock 60397977
hard memlock 60397977

Log in as the Oracle account owner (usually oracle) and use the following command to verify the value of memlock:

$ ulimit -l
60397977

If your system is running Oracle Database 11g or later, disable AMM by setting the values of both of the initialization parameters memory_target and memory_max_target to 0.

If you start the Oracle Database instances with a server parameter file, which is the default if you created the database with the Database Configuration Assistant (DBCA), enter the following commands at the SQL prompt:

SQL> alter system set memory_target=0;
System altered.
SQL> alter system set memory_max_target=0;
System altered.

If you start the Oracle Database instances with a text initialization parameter file, manually edit the file so that it contains the following entries:

memory_target = 0
memory_max_target = 0

Verify that all the Oracle Database instances are running (including any Automatic Storage Management (ASM) instances) as they would run on the production system.

Create the file hugepages_settings.sh with the following content (taken from the My Oracle Support (MOS) note 401749.1).

#!/bin/bash
#
# hugepages_settings.sh
#
# Linux bash script to compute values for the
# recommended HugePages/HugeTLB configuration
#
# Note: This script does calculation for all shared memory
# segments available when the script is run, no matter it
# is an Oracle RDBMS shared memory segment or not.
# Check for the kernel version
KERN=`uname -r | awk -F. '{ printf("%d.%d\n",$1,$2); }'`
# Find out the HugePage size
HPG_SZ=`grep Hugepagesize /proc/meminfo | awk {'print $2'}`
# Start from 1 pages to be on the safe side and guarantee 1 free HugePage
NUM_PG=1
# Cumulative number of pages required to handle the running shared memory segments
for SEG_BYTES in `ipcs -m | awk {'print $5'} | grep "[0-9][0-9]*"`
do
   MIN_PG=`echo "$SEG_BYTES/($HPG_SZ*1024)" | bc -q`
   if [ $MIN_PG -gt 0 ]; then
      NUM_PG=`echo "$NUM_PG+$MIN_PG+1" | bc -q`
   fi
done
# Finish with results
case $KERN in
   '2.4') HUGETLB_POOL=`echo "$NUM_PG*$HPG_SZ/1024" | bc -q`;
          echo "Recommended setting: vm.hugetlb_pool = $HUGETLB_POOL" ;;
   '2.6') echo "Recommended setting: vm.nr_hugepages = $NUM_PG" ;;
    *) echo "Unrecognized kernel version $KERN. Exiting." ;;
esac
# End  

Make the file executable, and run it to calculate the recommended value for the vm.nr_hugepages kernel parameter.

$ chmod u+x ./hugepages_setting.sh  
$ ./hugepages_settings.sh
.
.
.
Recommended setting: vm.nr_hugepages = 22960

As root, edit the file /etc/sysctl.conf and set the value of the vm.nr_hugepages parameter to the recommended value.

vm.nr_hugepages = 22960

Stop all the database instances and reboot the system.