XenForo xenforo website speed boost

[unph]

goto control panel/Cpanel / root directory
find src/config.php and paste this code

$config['cache']['enabled'] = true;
$config['cache']['frontend'] = 'Core';
$config['cache']['frontendOptions']['cache_id_prefix'] = 'xf_';
$config['cache']['cacheSessions'] = true;
$config['cache']['backend'] = 'File';
$config['cache']['backend'] = 'Apc';
$config['cache']['backend'] = 'Memcached';
$config['cache']['backendOptions'] = array(
    'compression' => false,
    'servers' => array(
        array(
            // your memcached server IP /address
            'host' => 'localhost',

            // memcached port
            'port' => 11211,
        )
    )
);

 

[ngbaze]

goto control panel/Cpanel / root directory
find src/config.php and paste this code

$config['cache']['enabled'] = true;
$config['cache']['frontend'] = 'Core';
$config['cache']['frontendOptions']['cache_id_prefix'] = 'xf_';
$config['cache']['cacheSessions'] = true;
$config['cache']['backend'] = 'File';
$config['cache']['backend'] = 'Apc';
$config['cache']['backend'] = 'Memcached';
$config['cache']['backendOptions'] = array(
    'compression' => false,
    'servers' => array(
        array(
            // your memcached server IP /address
            'host' => 'localhost',

            // memcached port
            'port' => 11211,
        )
    )
);

Where should i paste the code inside config file above or below ?

 

[XenForo]

below

below

 

[ngbaze]

below

Thank you

 

[HaXorx]

Thanks, brother.
But If I need to clear cache what should to do?