Mongo DB Server Startup Warnings

Question

I\'ve seen others with startup warnings but I can\'t seem find anything on this one. A few notes I\'m running on Ubuntu 14.04 my mongo version is 3.0.5 (I\'ve also tried 3.0

Answer 1

I am adding my solution as it may be helpful for those who look for an alternative solution using tuned.

For RHEL 7 virtual machines I use this solution, it should work for non-VMs also. There is a tuned daemon running on the servers and I use that to address the issue.

I put the following 2 files into the "/etc/tuned/mongodb" folder. The .conf file is referencing the "virtual-guest" settings that came with the builds on the VM farm, to preserve the settings that are necessary for VMs and then I change only the parameters that are needed for MongoDB. The script part is necessary as the only way to change the defrag parameter was through script.

# /etc/tuned/mongodb/tuned.conf
[main]
include=virtual-guest

[vm]
transparent_hugepages=never

[script]
script=mongodb.sh

and

#!/bin/sh
# /etc/tuned/mongodb/mongodb.sh

. /usr/lib/tuned/functions

start() {
    echo never > /sys/kernel/mm/transparent_hugepage/defrag
    return 0
}

stop() {
    return 0
}

process $@

Make the "/etc/tuned/mongodb/mongodb.sh" executable and make the "/etc/tuned/mongodb" folder recursively owned by root:root.

Then use the "tuned-adm" command to check and change the active profile.

sudo tuned-adm active
Current active profile: virtual-guest

then

sudo tuned-adm profile mongodb

then

sudo tuned-adm active
Current active profile: mongodb

After this, the huge-pages settings should be OK for MongoDB.