[Lou]Force-Building over water causes massive UPS drop in relation to how much landfill is required

[Averycoolname]

Whenever I have a blueprint and try to Force-Build it over water, I drop anywhere from 1 UPS all the way up to 55 UPS depending on how much landfill is required to Force-Build it.
If I have just some landfill required, my UPS doesnt drop at all.
But if its around 200 placable buildings (belts/foundries/assemblers/beacons) then I start seeing a noticable UPS drop. (my 4x4 nuclear reactor blueprint has a pretty noticable UPS drop, and that one has 82 turbines, 48 heat exchangers, 200 pipes, and some other stuff)
If its around 800 placeable buildings, like my city block foundry blueprint with 200 beacons and nearly 500 belts, if that entire blueprint requires landfill I drop down to 5 UPS.

My game is sitting on 60 UPS otherwise, and the UPS drop happens as soon as I press Shift over water and my UPS returns the moment I release Shift.

This is directly proportionate to how much landfill is required. Force-Building over land (to remove trees/rocks) doesnt affect my UPS at all.
The lag is only while I have the blueprint and is holding Shift over water. The lag disappears the moment I let go of Shift or the blueprint is placed.
This also happens in Space, I just tested it.

Playing on the latest version (at the time of posting) of Factorio: Space Age with no mods enabled except for the DLC mods (Space Age, Quality, Elevated Rails)

[Lou]

Thank you for the report. This seems to be the same case as 120391 . We made some performance improvements for 2.0.21