[FPS issue notice] FPS drop when proximity shield monsters appear in blight encounter.

Observation:
The proximity shield itself is not the cause of lag, but the hit from player and towers which "hit" a large number of enemies protected by proximity shield and cause CPU overload due to nature of the encounter.

Similar issue:
Same behavior can be observed when using AOE skills in highly dense area of enemies, but normally quickly subsides as enemies dies, less so with proximity shield case.

Suggestion:
Disable collisions on enemies under protection and let skills hit the shield itself to reduce number of "hit". (Such "collision disabled" behavior can already been observed as ability on certain enemies like Garukhan or Abyss golem).

Dxdiag snippet:
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System Information
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Operating System: Windows 10 Pro 64-bit (10.0, Build 19045) (19041.vb_release.191206-1406)
Language: English (Regional Setting: English)
System Manufacturer: ASUS
System Model: System Product Name
BIOS: 1661 (type: UEFI)
Processor: Intel(R) Core(TM) i7-14700K (28 CPUs), ~3.4GHz
Memory: 32768MB RAM
Available OS Memory: 32510MB RAM
Page File: 18228MB used, 22144MB available
DirectX Version: DirectX 12
DX Setup Parameters: Not found
User DPI Setting: 96 DPI (100 percent)
System DPI Setting: 120 DPI (125 percent)
DirectX Database Version: 1.0.8
DxDiag Version: 10.00.19041.4957 64bit Unicode

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Display Devices
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Card name: NVIDIA GeForce RTX 4090
Manufacturer: NVIDIA
Chip type: NVIDIA GeForce RTX 4090
DAC type: Integrated RAMDAC
Device Type: Full Device (POST)
Device Status: 0180200A [DN_DRIVER_LOADED|DN_STARTED|DN_DISABLEABLE|DN_NT_ENUMERATOR|DN_NT_DRIVER]
Device Problem Code: No Problem
Driver Problem Code: Unknown
Display Memory: 40396 MB
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Shared Memory: 16254 MB
Current Mode: 2560 x 1440 (32 bit) (59Hz)

i ll chime in but from a different aspect.

divine shrines that make monsters immune.

i hate this shrine by default but besides that. once i start smacking them, my game lags and the more i attack repeats (thanks multistrike) the laggier the game becomes. the laggier the game becomes the harder it is for me to regain control and it will just make me continue attacking even more.

this usually results in me dying.

say what you want about me attacking an invulnerable pack. thats on me, but when the game lags to the point i cant control my character thats the fault of the game.

it is not your PC lag, it is sever side lag that results in packets being delayed causing the game to wait before drawing stuff (i understand you play lockstep)

it is indisguishable for an untrained eye, even the 'fps graph' will 'prove' it is cpu time issue

it is not

spatial calcs, even simplified as in case of POE (circles are in fact squares stacked on top of eachother) are very expensive. usually you can fit into 'frame' because most mobs die in one hit, but these shields/divine shrines and mobs moving in and out of auras/elemental prolif make them repeat over and over making the server lag

there are compensation methods but at some point they will just fail leaving you with what you get


getting better CPU (or worse) wont change things on your end at all. what might 'alleviate' things - predictive networking mode when your PC actually can think on its own to some degree

blight is extreme case of this problem, to the point i unequip 'hex bloom support' from chars because this is one of the strongest game crashing spells ive seen

"

sidtherat wrote:

it is not your PC lag, it is sever side lag that results in packets being delayed causing the game to wait before drawing stuff (i understand you play lockstep)

it is indisguishable for an untrained eye, even the 'fps graph' will 'prove' it is cpu time issue

it is not

spatial calcs, even simplified as in case of POE (circles are in fact squares stacked on top of eachother) are very expensive. usually you can fit into 'frame' because most mobs die in one hit, but these shields/divine shrines and mobs moving in and out of auras/elemental prolif make them repeat over and over making the server lag

there are compensation methods but at some point they will just fail leaving you with what you get


getting better CPU (or worse) wont change things on your end at all. what might 'alleviate' things - predictive networking mode when your PC actually can think on its own to some degree

blight is extreme case of this problem, to the point i unequip 'hex bloom support' from chars because this is one of the strongest game crashing spells ive seen

thanks for the insight, though can't say I agree with your conclusion. Spherical body collision detection is the simplest and cheapest form of collision detection from my experience (way cheaper than cube body when using squared distance), so unless PoE is made in a garage by college students I trust they don't do that kind of hacky stuff.
Besides, if the event of enter / exit range of the aura is the cause of the problem it would be laggy just from them being on the screen, not only when they get hit by skill or towers. Further more, the players themselves are more often than not a walking pillar of multiple auras, so if what you said applies here, high minion count builds like skeleton, SRS or phantasm would experience constant lag at similar magnitude for just playing the game.

I do not have the source code or know how the game work so this is just my suggestion from what I observe in the game. GGG have full decision on what they going to do with it, I simply notice an issue from my experience in game.

high minion count builds WERE a problem, GGG fixed it by applying interval on on/off for minion aura checks - i vaguely remember that the interval is as long as ~.5second now
because it did precisely what you describe - it kinda didnt work to the point of crashing


imo poe's engine is fine, well refined. but there is a limit, actual mathematical limit to what you can squeeze into 1 frame, even on a modern cpu and POE does not guard itself against scenarios that exceed that.


but it is a cloud distributed thin-client, using as little threads as possible on a shared most likely virtualised infra. home pc with all these cores, thread pools, ample and exclusive L1/2/3 caches do not compare

and blight is notorious to all this because there are f..tons of mobs, all going in and out from various tower auras, burning grounds and auras of their own - this is the baseline computing cost. already bigger than any other content in the game.

then there are all your 'nearby' things

the proxy shield stuff you describe is put on top of that - if these mobs dont die quickly. poison prolif + corpse destruction is my choice for ravaged maps, it is the safest and can bypass proxy shields.


what ggg could do - is to tone down rares with auras (for blight or in general). these were the problem since 1.0, these are problem now. you simply cannot cheat math and there is a finite cpu cycles per frame available. once you exceed that, you start getting stutters (compensation tries to catch up on your end) but after that - its no bueno