After upgrading from 8930 to 9008 I see an increase in CPU usage.
For now it doesn't seem to be anything to worry about, but I prefer to report it for information.
Below is the hourly graph of the last few days, where you can see exactly the transition from 8930 to 9008:
Gabriele Maoret - Head of SysAdmins at SERSIS
Currently manages 6 SmarterMail installations (1 in the cloud for SERSIS which provides services to a few hundred third-party email domains + 5 on-premise for customers who prefer to have their mail server in-house)