Hello! I was just wondering if PocketMine can use more than one core in one server, I'm not quite aware of this and I just want to make sure
Ah, at first I didn't understand it without a clarification. Well, then the answer is yes and no. As the matter of fact there is more than one thread in PocketMine, but it's not too much difference, since, [as far as I know], the majority of computing is done on a single, main, thread. So it will mainly use one CPU core.
Not quite accurate. They are also used for chunk packet prepare and compression, and also for general network compression if `async-compression` is enabled in pocketmine.yml.