# install OpCache PECL extension (see http://php.net/manual/en/opcache.installation.php)
# enable (if not already) OpCache PECL extension in `php.ini`
# disable `APC` extension (if not already) in `php.ini`
# confirm, that extension changes had desired effect by looking at `phpinfo()` result
# choose profile to use (`in-portal.full` or `in-portal.community`)
# checkout In-Portal 5.2.x via `in-portal` module and then run `php /tools/configure_profile.php profile_name` script using chosen profile
# install In-Portal 5.2.x
# confirm, that no Fatal Error happened in the process