Description:
------------
php install in /usr/local/lib/php
php ext in /usr/local/lib/php/ext

Have host catalog:
/home/myhost/{www,ext,log}, where "ext" its clone "/usr/local/lib/php/ext"

include ext in php.ini:
> extension_dir = /usr/local/lib/php/ext
> extension = apc.so
Result: extension loaded

set chroot in config php-fpm:
> chroot = /home/myhost
> chdir = /www
Result: extension loaded

delete string "extension = apc.so" in php.ini, and add in config php-fpm:
> php_admin_value[extension] = apc.so
Result: extension not loaded

Add extension_dir in php-fpm config:
> php_admin_value[extension_dir] = /ext
> php_admin_value[extension] = apc.so
Result: extension not loaded


Change extension_dir in php.ini:
> extension_dir = /ext
And include ext in config php-fpm:
> php_admin_value[extension] = apc.so
Result: extension loaded