Minecraft server not using enough ram

[verbal lintel]

Minecraft is a single thread game. Individual PLUGINS might use more threads if they're built well, but usually Minecraft won't use many threads.

[frank ridge]

Thank you for the fast reply! I had this same setup before and it was able to use up to at least 3 threads but again maybe it was just acting weird back then.
Got any idea about the ram tho?