Latest update caused extreme amounts of lag when Autosaving

When my game tries to autosave, it freezes for a solid minute. I have changed the frequency of the autosave, more and less often, and it didn't stop it from freezing up. This only started happening with the latest update; I've never had this problem before.

There is also another bug with slabs/stairs that was already reported, where if flowing water touches waterlogged slabs/stairs, the water continues to flow through the slab/stairs. This also started happening with the latest update. I don't know if it's connected, but I wanted to mention it just in case it was. Please look at the other report for a better description of this part.