Is the Transparent Huge Pages (THP) feature enabled on RHEL 6 (x86) 32-bit architecture ?

Is the Transparent Huge Pages (THP) feature enabled on RHEL 6 (x86) 32-bit architecture, also enabled on RHEL 5?

 SOLUTION 已驗證 - 已更新 2019年四月5日08:49 - 

​​English ​​

環境

• Red Hat Enterprise Linux 6 (x86) 32-bit
• Red Hat Enterprise Linux 5 (x86/x86_64) 32/64-bit
• Transparent Huge Pages (THP)
• redhat_transparent_hugepage

問題

• Is Transparent Huge Pages (THP) feature enabled on Red Hat Enterprise Linux 6 (x86) 32-bit architecture ?

• Why Red Hat Enterprise Linux 6 (x86) 32-bit server does not have "redhat_transparent_hugepage" directory inside /sys/kernel/mm/?

  Eg:

​​Raw​​

# cat /sys/kernel/mm/redhat_transparent_hugepage/{defrag,enabled}
cat: /sys/kernel/mm/redhat_transparent_hugepage/defrag: No such file or directory
cat: /sys/kernel/mm/redhat_transparent_hugepage/enabled: No such file or directory
      

• Is Transparent Huge Pages (THP) feature enabled on Red Hat Enterprise Linux 5 (x86/x86_64) 32/64-bit architecture ?

決議

• The Transparent Huge Pages (THP) feature is not present on the 32-bit (x86) version of Red Hat Enterprise Linux 6. Install the 64-bit (x86_64) version to enable this feature.
• The Transparent Huge Pages (THP) feature is not present on the 32/64-bit (x86/x86_64) version of Red Hat Enterprise Linux 5.

根源

• The kernel configuration item "CONFIG_TRANSPARENT_HUGEPAGE" is not present in Red Hat Enterprise Linux 6 (x86).

  Raw

  # grep -i huge /boot/config-2.6.32-358.el6.i686 CONFIG_HUGETLBFS=y CONFIG_HUGETLB_PAGE=y

• The kernel configuration item "CONFIG_TRANSPARENT_HUGEPAGE" is enabled on Red Hat Enterprise Linux 6 (x86_64).

  # grep -i huge /boot/config-2.6.32-279.9.1.el6.x86_64 CONFIG_TRANSPARENT_HUGEPAGE=y CONFIG_HUGETLBFS=y CONFIG_HUGETLB_PAGE=y # grep -i huge /boot/config-2.6.18-194.el5 CONFIG_HUGETLBFS=y CONFIG_HUGETLB_PAGE=y # uname -a Linux localhost 2.6.18-194.el5 #1 SMP Tue Mar 16 21:52:39 EDT 2010 x86_64 x86_64 x86_64 GNU/Linux