12. PHP-FPM Optimization

I generally set following values in /etc/php/7.1/fpm/pool.d/www.conf file according to RAM of server and keep pm = dynamic:

16 GB RAM

pm.max_children = 750
pm.start_servers = 40
pm.min_spare_servers = 20
pm.max_spare_servers = 60
pm.max_requests = 1000

8 GB RAM

pm.max_children = 375
pm.start_servers = 40
pm.min_spare_servers = 20
pm.max_spare_servers = 60
pm.max_requests = 1000

Note: Above specific values are according to my experience, I prefer to avoid having over-broad discussion.