Disable transparent huge pages in TokuMX

Question

When I try to start the mongod server by giving ./mongod --dbpath /nlu/ind/mongodata I get an error saying

TokuMX will not run with transparent huge pages enabled. Tue Aug 20 10:47:34 [initandlisten] Please disable them to continue. Tue Aug 20 10:47:34 [initandlisten] (echo never > /sys/kernel/mm/transparent_hugepage/enabled) Tue Aug 20 10:47:34 [initandlisten] Tue Aug 20 10:47:34 [initandlisten] The assertion failure you are about to see is intentional

Please let me know how to sort this. Thanks in advance for your help. I have 3 directories in /sys/kernel/mm/ and they are hugepages ksm redhat_transparent_hugepage

Answer 1

As the message states, you need to do the following:

sudo bash -c 'echo never > /sys/kernel/mm/transparent_hugepage/enabled'

You can cat /sys/kernel/mm/transparent_hugepage/enabled to see the current setting and to make sure that your echo worked.

The setting will be cleared when you reboot when setting it in this manner. TokuMX sets this in it's init script.

Answer 2

Please visit this question for a more thorough discussion: https://unix.stackexchange.com/questions/99154/disable-transparent-hugepages

You can add transparent_hugepage=never to the GRUB_CMDLINE_LINUX_DEFAULT option in /etc/default/grub and run sudo update-grub

To test that it took effectcat /sys/kernel/mm/transparent_hugepage/enabled should look like this: always madvise [never]