turn on mysql slow query log

gistfile1.txt

[mysqld]
long_query_time=1
log-slow-queries=/var/log/mysql/log-slow-queries.log

and:
mkdir /var/log/mysql
touch /var/log/mysql/log-slow-queries.log
chown mysql.mysql -R /var/log/mysql

or:
[mysqld]
log-slow-queries = slow.log
long_query_time = 20
log-queries-not-using-indexes