max_input_vars (PHP7 and PHP.ini)

hello,
i ve got an issue when i launch for the first time projeqtor (Debian 9, PHP7)

seems all is right except max_input_var

PHP version is 7.0.19-1 : OK
Module PDO is available : OK
Module PDO for 'MYSQL' is available : OK
Module MBSTRING is available : OK
Class ZipArchive is available : OK
Module DOMDocument is available : OK
GD Library is available and correctly installed : OK
Module IMAP is available : OK
Module OPENSSL is available : OK
Module XML is available : OK
max_input_vars=1000 is too small - value should be at least 2000, 4000 recommended - check your php configuration (php.ini)
max_execution_time=30 : OK
memory_limit=128M : OK
file_uploads=1 : OK
session.auto_start is disabled : OK
magic_quotes_gpc is disabled : OK
register_globals is disabled : OK

i know where is my php.ini file (/etc/php/7.0/apache2/php.ini ) but unfortunaly i m unable to find the "max_input_vars" in !!!
Any idea where it is ?