How do I enable transparent huge pages by default on Ubuntu?

Question

~$ uname -a
Linux yoda 3.5.0-23-generic #35~precise1-Ubuntu SMP Fri Jan 25 17:13:26 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
~$ cd /sys/kernel/mm/transparent_hugepage/
/sys/kernel/mm/transparent_hugepage$ ls
defrag  enabled  khugepaged
/sys/kernel/mm/transparent_hugepage$ cat enabled 
always [madvise] never
/sys/kernel/mm/transparent_hugepage$ sudo echo always > enabled 
-bash: enabled: Permission denied
/sys/kernel/mm/transparent_hugepage$ sudo ls
[sudo] password for <...>: 
defrag  enabled  khugepaged
/sys/kernel/mm/transparent_hugepage$ sudo ls
defrag  enabled  khugepaged
/sys/kernel/mm/transparent_hugepage$ sudo echo always > enabled 
-bash: enabled: Permission denied
/sys/kernel/mm/transparent_hugepage$ cat enabled 
always [madvise] never

In `sudo echo always > enabled`, the I/O redirection runs as the current user, not root. Try `sudo bash -c "echo always > enabled"`. — Dr Kitty, Apr 18 '13 at 00:19
@DrKitty I wish you had given this as an official Answer so I could vote it up! — Daniel, Sep 06 '13 at 15:12
You can also use `echo always | sudo tee /sys/kernel/mm/transparent_hugepage/enabled`. Can't remember where I saw it being used that way, but it beats `sudo su -c "..."` IMHO. I added as a comment because this is a runtime setting, Rancor has provided the right answer for setting it as default. — tdaitx, Oct 08 '14 at 16:40
@DrKitty if you make u make ur answer an answer i'll upvote it — Jose Martinez, Mar 06 '15 at 06:44
The command line "sudo echo always > enabled" should be : sudo sh -c "echo always > enabled" — Rachid K., Dec 19 '20 at 21:13

score 21 · Answer 1 · answered Sep 06 '13 at 07:04

21

Adding the following:

transparent_hugepage=always

to GRUB_CMDLINE_LINUX_DEFAULT in your:

/etc/default/grub

and doing a:

update-grub

should do the trick.

answered Sep 06 '13 at 07:04

score 5 · Answer 2 · edited Aug 08 '14 at 16:37

5

sudo su
password: [....]
echo always > /sys/kernel/mm/transparent_hugepage/enabled

edited Aug 08 '14 at 16:37

Joel

4,732
9
39
54

answered Aug 08 '14 at 16:13

Lee

331
3
3

2

Beware that doing this will only enable THP until the next reboot. The question was how to enable it by _default_, for which @Rancor answer is the right one. – tdaitx Oct 08 '14 at 16:49

score 1 · Answer 3 · answered Mar 06 '15 at 17:55

1

Add this to your /etc/rc.local:

echo always > /sys/kernel/mm/transparent_hugepage/enabled

answered Mar 06 '15 at 17:55

egors

55
5

How do I enable transparent huge pages by default on Ubuntu?

3 Answers3