Starting a new thread because I haven't seen this before on my C-8.
Free Memory dropped this morning to 17. There wasn't really anything going on at the time that would have caused a spike like that and I can't see anything in the logs. I rebooted and everything appears to be back to normal now. The hub did seem to take a longer time than usual to reboot.
It may be unrelated, but I've also noticed that cloud backups have stopped. I have Hub Protect transferred over from my C-5. I have cloud backups scheduled for every 3 days. The last cloud backup was on March 13th. I manually created one this morning and entered a support ticket.