19w03c is now playable on servers, though not perfect. Dimension transfer is still slow but other than that it seems improved
Usually VSync would fix this
It's not in the changelog for 19w03B so that needs to get added to this
It's still extremely slow in 19w02a
Still occurring with 18w48a
Fairly certain that this is intended behavior, it isn't actually unlimited as it stops at the world height limit
Still occurring with 18w46a in fact it is a bit worse than previous snapshots
(This is not just on integrated servers but also on dedicated)
Also to add to this... transferring dimensions is extremely slow. A few seconds to enter/leave the nether
Confirmed with 18W14A
Well the issue is indeed that the server ran out of memory and the simple solution is to assign more if you have it available. I recommend at least 2G depending on the number of players connected.
Attempt to use this and see how it works:
-Xms512M -Xmx2G -jar minecraft_server.18w11a.jar nogui
This is happening on all Operating Systems
Confirmed for 19w04a