Well, basically, that means you have too low memlock limit setting in your OS. This can be easily fixed in two steps:
1) Edit /etc/security/limits.conf file and add to the end:
* hard memlock unlimited * soft memlock unlimited
2) Add a line to the /etc/pam.d/common-session file:
session required pam_limits.so
that'll make sure your limits are loaded for every session.
3) Reboot the server.
4) Check your limits via:
if all went well it should return unlimited as an output.
P.S. As always, do all changes on your own risk and don't forget to backup before experimenting.