restart php fpm processs. code example
Example 1: ubuntu restart php-fpm
service php-fpm restart # typical
service php5-fpm restart # debian-style
service php7.0-fpm restart # debian-style PHP 7
service php7.2-fpm restart # debian-style PHP 7.2
service php7.4-fpm restart # debian-style PHP 7.4
Example 2: how to restart php-fpm on ubuntu
sudo /etc/init.d/php-fpm restart