For better MySQL performance, we recommended starting with clean MySQL installation using the following option in /etc/my.cnf:

innodb_buffer_pool_size = 2G ( ~ 50% of RAM available on host)
innodb_additional_mem_pool_size = 20M
innodb_log_buffer_size=16M
innodb_thread_concurrency=8
innodb_file_per_table

max_allowed_packet = 64M

Also, [mysqld] and [client] sections should contain the same "socket = /path/to/mysql.sock". See example bellow:

[mysqld]
socket=/var/lib/mysql/mysql.sock

[client]
socket=/var/lib/mysql/mysql.sock