Connect to our server using SSH and do this command:
for conf in /etc/php-fpm.d/*.conf \
/etc/php/*/fpm/pool.d/*.conf \
/opt/plesk/php/*/etc/php-fpm.d/*.conf
do
[ -f "$conf" ] || continue
domain=$(basename "$conf" .conf)
# Use \K to match memory_limit value after "memory_limit] = "
mem=$(grep -Po 'memory_limit]\s*=\s*\K\S+' "$conf" 2>/dev/null)
echo "$domain: $mem"
done
You retrieve a list of domains and his Memory Limit. If no Memory Limit is specified on the domain in the list, the domain is using the Default Memory limit on the system.