Create new client and then 'change owner' of website and mysql from 'admin' to new client. And then, to minimize memory usage for php-fpm, change 'php-ftpm type' to 'ondemand' for 'admin'.
[/quote]
It seems changing in /opt/configs/php-fpm/conf/php71m/php-fpm.d/admin.conf fixed the problem.
Such config works the best:
pm = ondemand
pm.max_children = 100
pm.start_servers = 5
pm.min_spare_servers = 5
pm.max_spare_servers = 35
pm.max_requests = 20000