I am seeing very long save times when trying to exit a world in the snapshot releases. I have seen this since trying out the snapshots a couple weeks ago and is still occurring with the latest version. It takes anywhere from 45 seconds to over 1 minute to exit a world.

Steps to create issue:

1. Create new world using default settings
2. Exit game

I have tried various options such as game mode and world type settings as well as re-creating  a 1.15.2 world and I have the same issue. Logging out of worlds with version 1.15.2 only takes a few seconds.

Including a screenshot of the "F3" screen and the world gen settings.

Computer Specs:

• Lenovo Legion Y730
• Intel Core i7-8750M
• GeForce GTX 1050 Ti
• 16 GB RAM
• 256 GB SSD ("/") and 2TB hard drive ("/home")