[MC-194435] Fluid lag spike in 1.16.1

I made a general mobs farm designed by gnembon on the single player and also on a server:

Version 1.16.1 on single player: https://streamable.com/qd9t1i

Version 1.16.1 on single player (no mod): https://streamable.com/k2cc4n

(i also turn the mob spawning rule off to test on single player, the fluid cause the lag spike)

Comments 2

Thank you for your report!
However, this issue is Invalid.

Your game, launcher and/or server is modified.
If you can reproduce the issue in a vanilla environment, please create a new ticket.

Any non-standard client/server/launcher build needs to be taken up with the appropriate team, not Mojang Studios or the Bugtracker.
Any plugin or resource pack issues need to be addressed to the creator of the plugin or resource pack.
If you have problems on large servers, such as The Hive and Hypixel, please contact them first as they run extensively modified server software.

Quick Links:
📓 Issue Guidelines – 🛠 Community Support – 📧 Customer Support – ✍️ Feedback and Suggestions – 📖 Game Wiki
💬 Mojira Subreddit – 💬 Mojira Discord

i added the vanilla version too on the Description, it also does cause the lag spike