We calculate based on the following formula:
pm.max_children = Total RAM dedicated to the web server / Max child process size
To calculate the amount of RAM used by each 1 php-fpm child process
ps –no-headers -o “rss,cmd” -C php-fpm | awk ‘{ sum+=$1 } END { printf (“%d%s\n”, sum/NR/1024,”M”) }’
To raise the limit globally, change directadmin.conf value first:
cd /usr/local/directadmin/
./directadmin set php_fpm_max_children_default 100
cd /usr/local/directadmin/custombuild
./build rewrite_confs
service php-fpm74 restart
File log PHP FPM
tail -f /var/log/php-fpm/error.log
Config file
[php-fpm-pool-settings]
pm = dynamic
pm.max_children = 25
pm.start_servers = 10
pm.min_spare_servers = 5
pm.max_spare_servers = 20
pm.max_requests = 500