A fresh world (i.e. not upgraded from 1.12.2) on a 1.13-pre8 vanilla server using the official server jar runs at 8-14 tps on my computer, where it would run the same world in singleplayer at 20. The same computer can also run a vanilla 1.12.2 server with a normal world at 20 tps without problems.

Steps:

1. Create a new world in 1.13-pre8, using default generation settings
2. Run debug profiler or observe the latest.log file
3. Exit and start the same world on a 1.13-pre8 server
4. Run debug profiler or observe the console
5. Optionally, compare results with a 1.12.2 server jar, with a similar world
6. The server should be skipping more ticks and having a hard time keeping up compared to the singleplayer integrated server.

Issue not related to MC-118106 or MC-132135