Massive FPS drops when memory required from GPU is more than the VRAM

thats the problem sadly, nothing is doing anything for this problem :frowning:

I can set it to medium even and absolutely nothing will changeā€¦
Lets say i do this:

  • load into the airport it shows me 3.5GB vram used and everything is fluid
  • move camera to outside view and now its already at 5GB
  • switch to cockpit again and its at 6ā€¦
  • now any more switch, even to the exact same camera like before, will add another amount and eventually reaches 7GB and overflows. Now it may show things like 7250 / 7100 MB Vram. And its stuck there. For like 20 seconds or until i alt-tab, then its quicker. Maybe 5 to 10 sec. Then it returns to 3.5Gb and the game repeats.

If i go to settings now and decrease LOD, texture quality, shadows, reflections and whatnot, nothing will change at allā€¦ The sim looks stupid but the problem remains.

I can fly in the 737 most of the time but in the Fenix those 70-80% of airports that show this are a sad truth.

What drives me nuts is that i know this wasnt the case always. When the Fenix released, even after the first update i had AIG traffic on at 100%, high res Fenix vc textures, cabin active and 200 LOD. And it never happened.

Now i deinstalled AIG, deactivated the cabin, only use 4k textures, use low res textures for vc, set the settings lower and it happens all the timeā€¦

Its not really a Fenix thing thoughā€¦ i get it also on a tiny amount of payware airports in the 737ā€¦ So there has to be some underlaying problem with the sim.

It will drive me crazy one day ^^ Because ive tried so many things alreadyā€¦

No modern game is showing this behaviour, its an msfs thing on my pc.

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Impressive analysis of the problem :+1:

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Moved to #bugs-and-issues:performance.

Since su10 my rtx 3070ti vram usage went through the roof.

Ddu, new driver, rollback nothing works. Mainly happens on flights longer than an hour or in the vicinity of large airports.

Exactly as @Senchay6131 describes with camera switching msking it worse.

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Thatā€™s what Iā€™m also getting and Iā€™m only on 6GB Vram and so that means the aircraft is taking it all up straight away. Yet loading in is all fine with 30FPS and what I dislike about it since I always run it in window mode is that when FPS drops, it doesnā€™t go back up and gets stuck till luck comes and goes backup or it doesnā€™t and FPS becomes lower and lower till itā€™s 5 FPS

Is DX12 still BETA?

Think it will be fixed in SU11, actually running the first BETA and the VRAM is lower (Dublin with Scenery was 4.5 to 5 GB maximum and now during Cruise around 4.5 GB). Also have the RTX 3070ti running DX12 and DLSS on Quality.

FPS were at around 30 and in Cruise at around 50 both in Cockpit View at the PMDG 737.

Not all people going to get the same, I say those that are on 6GB cards and whatnot will still get bad performance

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Do you have the same issue if you follow the OPā€™s steps to reproduce it?

Yes but with SU11 beta

Provide extra information to complete the original description of the issue:

just tested SU11 beta, this VRAM usage problem is not solved in SU11 beta even though in release notes it claims it is. in fact my performance is worst in SU11 than SU10. 99% VRAM usage in KLAX and 96% in anchorage (same as SU10). But with SU10 I used to get 43-45fps dipping to 29-30 when panning camera at KLAX. SU11 Iā€™m getting 38-40 sometimes dipping down to 15fps when panning camera causing stutters. 4K, DLSS quality, 100% LOD. Ryzen 5600X, RTX2080-S.

Are you using DX12?

Yes

Are you using DLSS?

Yes quality

If relevant, provide additional screenshots/video:



Your GPU graphs are different to mine, could you check something for me and let me know what you see.
Let explain, when I switch to DX12 my 3D graph drops to below 20% but when I change the ā€œVideo Decodeā€ graph to ā€œgraphics 1ā€ I see the bulk of my GPU load in this graph. This gives a total of 110% usage. I have great performance and never any CTD or stutters.
Thanks

My 8GB of VRAM runs at 7.3GB in DX12 and uses 3+GB of the 15GB GPU reserved ram. I do not know if this is what it should do but it runs smoothly.

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That is exactly what my 3070 does.

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You have to look at the total use of vram, when it exceeds 8gb in your case you have a vram overflow. Dedicated memory value should be higher as shared memory is used by ram such as vram. It makes it slow! We see that the dedicated memory often remains low but still there is a use of shared memory.

This is still very much a problem in SU11 beta. If they donā€™t get this sorted by next week, well be stuck with this problem until at least SU12 next year.

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Issue is still present in SU11. When setting graphic settings too high, dramatic drop in FPS that can only be restored by exiting the flight (not by setting graphic settings lower in flight).

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Wonderfulā€¦ DX12 is required for my home cockpit build. Was hoping the memory allocation fix in SU11 was indeed a fixā€¦

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I have this problem also under DX11 with a 10 GB RTX 3080 when I am in VR. Sometimes on demanding airports and bad weather like heavy rain, the VRAM allocated by the sim exceeds the available amount of VRAM and then the FPS drop from 40 to 15 or 10 on my rig. If I change the live traffic or the weather then maybe the VRAM demand drops below the existing amount and the fps return to 40.
So this problem is still present in the newest beta 1.30.11.0 under DX11 in VR and a card with 10 GB VRAM.

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Turn down the texture quality, as this has a significant impact on VRAM usage. Terrain LOD also seems to have a big impact on VRAM usage as well.

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What the heck happened to the FPS in SU11 - Community Support / Tech Support - Microsoft Flight Simulator Forums

Here I propose a solution for the problem of FPS drop and loss

Have if it works for you.

Specific issue fixed in SU11. Closed as resolved.