Real Work allocations....

I have change the value of max input to 4000,
on etc/php5/apache2/php.ini
but it is not work

i did, i, terminal:
sudo /etc/init.d/apache2 stop

and

sudo /etc/init.d/apache2 start

and it do not work, what's problem

this is what I have on the log file:

2015-04-27 19:01:54 ***** ERROR ***** GD Library not enabled - impossible to draw charts
2015-04-27 19:01:54 ***** ERROR ***** GD Library or FreeType Librairy incorrect or not correctly installed - impossible to draw charts
2015-04-27 19:02:13 ===== TRACE ===== WARNING - Left work not retrieved from screen
2015-04-27 19:02:13 ===== TRACE ===== - Maybe max_input_vars is too small in php.ini
2015-04-27 19:02:13 ===== TRACE ===== - Assignment #39 on Activity #25 for resource #6 - PREVOSTO Jonathan
2015-04-27 19:02:13 ***** ERROR ***** ERROR *****
2015-04-27 19:02:13 ***** ERROR ***** on file '/var/www/projeqtor/tool/saveImputation.php' at line (84)
2015-04-27 19:02:13 ***** ERROR ***** cause = Error - Maybe max_input_vars is too small in php.ini

so I have an other PHP.ini ?