CentOS and MySQL 5.6
New MySQL installs might not have any included my-*.cnf files.
We've added a few from MySQL 5.5 which seem to work with 5.6, eg:
cp /etc/my.cnf /etc/my.cnf.old
wget -O /etc/my.cnf http://files.directadmin.com/services/all/mysql/my-huge-5.5.cnf
Press ctrl-c to exit insert mode. Then press shift-Z shift-Z to save and quit. Restart mysqld:
Redhat:
/sbin/service mysqld restart