Hi,
I started 4 instances using Redhat 6.4 community AMI on AWS. Installed ambari on the 5th one. It was all going fine. Then, during the host checks, Ambari mentions that all 4 are running THP. On some digging around, we realized that THP is not playing well with Hadoop, among other services and it would be good to disable it.
We tried the first method which was often mentioned everywhere, which is as follows:
echo never > /system/kernel/mm/transparent_huge_page/enabled.
This didn’t work.
Then, we did the same to the file /system/kernel/mm/transparent_huge_page/defrag and that didn’t work out either.
After a set of restarts and non-work arounds, we edited the file /etc/rc.local to do the following:
if test -f /sys/kernel/mm/transparent_hugepage/enabled; then
echo never > /sys/kernel/mm/transparent_hugepage/enabled
fi
if test -f /sys/kernel/mm/transparent_hugepage/defrag; then
echo never > /sys/kernel/mm/transparent_hugepage/defrag
fi
After this we restarted the machine and Ambari still says that transparent_huge page is enabled!
What is the right way to go about disabling THP on redhat 6.4 for Ambari?
Thanks a lot for your help.