We have a massive performance problem on our realm. It began long before 1.16 went live. But with 1.16 it still persists. Our main storage house is quite big with lots of chests, frames and a large map room.

First floor: 190 frames, 36 maps in frames
Second floor: 4 frames
Cellar floor: 67 frames
Sub cellar floor: 146 frames
Map room: 257 frames, 145 of them with maps

Everytime someone gets into the storage house or its chunk, the whole server starts to "hick up" ...  even in nether. We are getting heavy lags. Leaving the chunk brings back player the smooth performance and everything is ok. Are there known issues with wall-frames or maps on wall-frame on specific?

If this isn't a bug and it's a known problem with maps or frames:
which one needs more performance?

a) Generally frames themselves 
b) Generally frames with items
c) Specifically Frames with maps