I’m running Openhab 2.3.0 based on a Openhabian installation.
All Updates are applied. Hardware is a Raspberry Pi 3B+. I’m using an USB attached SSD as system drive.
I use a lot of Bindings. The Load of the Raspi is never lower than 1.
Example:
At first you could disable bindings and rules one at a time and see if that makes a difference. Looking at your thread list I’d start with something that relates to Frizbox.
There’s gazillion potential reasons so you need to investigate further what’s the conditions/recent actions to cause this, otherwise it’s just pure guessing and digging in the dark, and noone neither wants nor can do that except yourself.
One frequently met reason though is that Java recompiles rules. That’ll happen whenever you edit rules and config files which you shouldn’t do interactively.
See this thread for details and check if that edit method mentioned makes a difference for you.
PS: and we expect people to search the forum before asking for help, and I guess you would have found that thread yourself if you had.