Disable THP on CentOS 6

For the impatient

Disable Transparent Huge Pages on CentOS 6

During Runtime

echo never > /sys/kernel/mm/redhat_transparent_hugepage/enabled
echo never > /sys/kernel/mm/redhat_transparent_hugepage/defrag

Surviving reboot

1. sudo vi /etc/init.d/disable-transparent-hugepages

2. #!/bin/sh
   ### BEGIN INIT INFO
   # Provides: disable-transparent-hugepages
   # Required-Start: $local_fs
   # Required-Stop:
   # X-Start-Before: mongod mongodb-mms-automation-agent
   # Default-Start: 2 3 4 5
   # Default-Stop: 0 1 6
   # Short-Description: Disable Linux transparent huge pages
   # Description: Disable Linux transparent huge pages, to improve
   # database performance.
   ### END INIT INFOcase $1 in
   start)
   if [ -d /sys/kernel/mm/transparent_hugepage ]; then
   thp_path=/sys/kernel/mm/transparent_hugepage
   elif [ -d /sys/kernel/mm/redhat_transparent_hugepage ]; then
   thp_path=/sys/kernel/mm/redhat_transparent_hugepage
   else
   return 0
   fi
   
   echo 'never' > ${thp_path}/enabled
   echo 'never' > ${thp_path}/defrag
   
   unset thp_path
   ;;
   esac

3. sudo chmod 755 /etc/init.d/disable-transparent-hugepages
4. sudo chkconfig --add disable-transparent-hugepages