Server was is not accessible for nearly an hour. All services are online again.
Problem 09:30 UTC
Received alert that server was under very high load again. On inspection found similar condition to what existed a few days ago on 28 May. Attempt to perform soft reboot left the server unresponsive; now awaiting data centre to perform a hard reboot.
Update 10:10 UTC
Server is back online. We are monitoring.
The situation with the server becoming every few days is very inconvenient and of course unacceptable. We are taking a deep look at everything again.