a server option to use more threaded

well i recently begin my journey on the server side of minecraft and one of the problem i face almost each time is that the sever only use one threaded on my cpu when it could use way more. A option to download a server that would allow minecraft to use 2-3-4 or more threaded would be nice for server owner. I could do better and faster pregen of my map , and having more player on one server