alt Hacker Newstirreno (1) guy here.
What you're seeing is normal bot behaviour, they constantly scan every website for different purposes. 100–500 requests per IP is nothing you should worry about or take any action against.
tirreno works on the backend, so sometimes we use it to analyze bot behaviour when they start doing something really suspicious, like massive requests (hundreds of thousands a day) or scanning all possible files/folder structures, which could easily result in half a million requests in short period of time.