[lou] [2.0.26] FPS drop with blueprint preview (Game render preparation)

[Gummiente27]

Hi,

I have a performance problem during big (204x204) blueprint preview (FullHD, AMD 5600x, Nvidia 1660 Super).

FPS go from 60 to 44 in new game (and in my actual game save from 60 to ~35) just by previewing the blueprint.

You can find the blueprint in the inventory/hotbar of the save file (Test) or in the dedicated file.

Slowdown does not occurr in map view.
I noticed I other F4 options enabled when taking the screenshot (show-clock, show-blueprint-grid and show-fluid-box-fluid-info), but in later tests I did not notice any performance impact difference when reproducing this issue with those two options disabled as well.

FPS doesn't improve whether the blueprint is completely on the screen or not, also zoom level doesn't change it.
All the extra time is spent in "Game render preparation".

Edit:
Filling up the blueprint with lots of solar/akkumulators, causes fps to tank even more, I've seen FPS below 20.
Also gets worse when hovering blueprint over area where it was already built.
I have not found any setting in graphics section which fixes this problem.

Edit 2:
This issue was originally observed with 2.0.20. 2.0.25 still shows same behaviour. Updated title.

Best graphics options comapred to "worst" graphics options show only adifference of 1 FPS (with worst options i get 45 FPS in my test world, with best i get 44)

Testing by removing different entity types from the blueprint, to me it seems like its mostly related to the amount of entites and not some specific entity.

In the test world it only lowers FPS.
(In my main world, these huge blueprints also lower UPS to be exactly same to FPS, maybe due to some mods forcing them to be synchronized.)

[Titan Uranus]

This seems related to the issue I have, I get low UPS when placing a blueprint over water, which is about the size of 3x3 roboport coverage.
(1440p, Ryzen 5800X3D, 4x8GB 3200Mhz RAM, Nvidia 3070)

When holding the shift key to place landfill and remove trees etc. with the blueprint, CPU usage on one core jumps to 95-99% and I get as low as 13.9 UPS, when not over water and holding shift CPU usage is still quite a bit higher on one core at about 42%, but still 60 UPS.

When not holding shift, wheather over water or not, CPU usage is only about 25% on the higest core. it is usually about 20% when just walking around and doing stuff or in remote mode, so 5% higher with a blueprint and not holding shift.

I am on version 2.0.20.

[Gummiente27]

I noticed it gets even worse with "Game render preparation" when the blueprint is hovered above a place where it got built already (i.e. hovering-over-empty -> hovering-over-built: 23ms -> 34ms, fps/ups 33 -> 25)

[Guenni7]

My ups goes down to 15 when I only want to place a roboport into my existing base.
I'm curious, could you try to place the same blueprint but without any roboports?

[Gummiente27]

My ups goes down to 15 when I only want to place a roboport into my existing base.
I'm curious, could you try to place the same blueprint but without any roboports?

Found no difference in blueprint preview performance. Robots present or not in preview was not observable in FPS. Both times still reduce FPS from 60 to 44.

[Gummiente27]

(used 2.0.26)

I've added another blueprint of 204x204 size without accidentally including an infinite chest.

In the test save i sent, preview takes ~20-21ms in "game render preparation", reducing fps from 60 fps to ~44 fps.

Holding shift, the "game render preparation" time increases from 20-21ms to 44-46ms, reducing fps even further down to 21 fps.

i did a few experiemnts, each time removing one type of item from the blueprint and looked at game render preparation times, these improvement numbers are obviously jsut me looking at then umber, and can be 0.5-1ms off, i did use best times of original blueprint2 and middle/worst times of modified blueprint2:

removing ~1k express underground belts - 4ms improvement
removing ~1.2k solar panels - 2ms improvement
removing ~1k akku - 1ms improvement
removing 885 fast inserters - 2ms improvement
removing 829 express belts - 2.5ms improvement
removing 554 filled effect spreaders - 2.5ms improvement
removing 477 rails - 1ms improvement
removing 442 electric ovens - 3-4ms improvement
removing 270 medium electirc poles - 2ms improvement
removing 238 fast underground belts - 1ms improvement
removing 227 bulk inserters - 0.5ms improvement
removing 144 chests - 0.5ms improvement
removing 136 express splitters - 0.5-1ms improvement

removing other items with less counts - no observable change change