apt-get install php5-mysql php5-fpm php5-gd php5-cli apache2-mpm-worker libapache2-mod-fastcgi

Create a php-fpm pool /etc/php5/fpm/pool.d/$USER.cnf

[$USER]
user = $USER
group = www-data
listen = 127.0.0.1:9000
listen.owner = www-data
listen.group = www-data

pm = dynamic
pm.max_children = 100
pm.start_servers = 35
pm.min_spare_servers = 15
pm.max_spare_servers = 35
php_value[session.save_handler] = files
php_value[session.save_path] = /var/lib/php/session/$USER
chdir = /

In Vhost:

ProxyPassMatch ^/(.*\.php(/.*)?)$ fcgi://127.0.0.1:9000/var/www/vhosts/MYDOMAIN.COM/public_html/$1

Enable/disable modules and restart services

a2dismod mpm_prefork php5 && a2enmod actions fastcgi alias mpm_event proxy_fcgi proxy

service php5-fpm restart
service apache2 restart

Don’t forget to enable “index.php” in your DirectoryIndex directive, if using PHP-FPM! Also, remove any PHP directives from Apache, and configure in PHP-FPM instead.