How to monitor a server with many virtual hosts?

Question

infographics

Initial: gentoo server, nginx, apache2, mysql - everything is as usual. spins several dozen hosts.
How to look at and build graphs on the subject of who is eating more resources?
Or here's another: how to see which of the database users gouge the base, that it fits sometimes?
Thanks in advance everyone)

Answer 1

cacti, nagios, zabbix, opsview