Avionics refresh rate much slower now

Sim Update 15 Beta Aircraft & Systems
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1

:wave: Thank you using the Bug section, using templates provided will greatly help the team reproducing the issue and ease the process of fixing it.

Are you using Developer Mode or made changes in it?

No

Which aircraft are you using that experiences this issue?

DA62
TBM 930
VL-3
L-39C Drop Bear
and all other builtin glass cockpit planes I’ve tried

Brief description of the issue:

Avionics refresh rate is much slower than before even with “GLASS COCKPIT REFRESH RATE” option set to “HIGH” (max value) when “Frame Generation” is ON.

(See video below, comparing beta with current version)

Note: it doesn’t seem to affect SVT.

Provide Screenshot(s)/video(s) of the issue encountered:

MAKE SURE YOUTUBE IS PLAYING THE VIDEO IN 1080P 60 FPS

Game is running at 60FPS and with the same graphics settings in both cases

Detailed steps to reproduce the issue encountered:

Make sure game is running at 60 FPS (or more), “GLASS COCKPIT REFRESH RATE” option is set to “HIGH”, and Frame Generation is enabled on settings.
Start a flight, take off, do some steep climb or dive, and look at airspeed/altitude gauges.
You’ll see they seem to refresh at ~11FPS

Are you using DX11 or DX12?

DX12

Are you using DLSS?

Yes, Frame Generation (No super resolution)

After some testing, I’ve realized the following:

When Frame Generation is OFF:
avionics refreshes at 20 FPS.

When it’s ON:
avionics refreshes at ~11FPS (maybe 10)

(both cases considering “game” is running at 60 FPS)

Before SU15 Beta, FG on gave me 60 FPS in avionics (motion artifacts were there, but not perceivable).
With FG off, it was 30 FPS before, and 20 FPS now.

So probably the raw framerate difference is hitting FG here.

Note: ATR 72 isn’t affected by this (maybe due to custom avionics), but every default (builtin) glass cockpit plane that I’ve tested has this problem.

Note 2: it also affects 787 avionics, but in this plane, even the throttle levers and the yoke seem to animate at a lower rate. It gives the impression the game is running slower, when in reality it’s running at 60 FPS.

Citation Longitude also has throttle levers animating poorly now.

I understand it might even be “by design” in order to improve performance, but it would be cool if there was some option to revert this behaviour to what it was before SU15 Beta, because not everyone needs this optimization. Not everyone has performance problems that are fixed only by lowering individual plane component’s refresh rate .

It’s like everyone is being limited in performance as if everyone had a Xbox Series S console, when there are people with highly capable hardware forced to see those low rate animations in avionics.

Thanks!

2

Same, using the Iris PC-21 the HUD is choppy now. No more smoothness even at High refresh…

3

Not really noticeable on the PFD’s to me but trying to pan a map around in the G3X is quite rough

4

i felt the same thing in the A32nx when rotating the heading knob.
it was noticably slower than ever.

1 Like
6

Seems to be smooth for me right now - cant notice what you showed in your video. Flying in the SR22T. Im using medium setting for displays and even then its smooth, tried high and still good. EDIT: i think i notice it now, especially on the inset map, it seems much less smooth. +1, good find.

7

At the highest cockpit refresh setting, the instruments already ran only every other frame. So 30fps would not be a regression from before, FYI.

8

Yes. Same performance issue here on Xbox-X refresh rate of the avionics is decreased compared to SU14. And both the yoke and the throttles look as they were stuttering compared to the outside.

2 Likes
9

I am no developer, but maybe this is intentional to help reduce memory usage/leaks/etc with SU15 improvements?

10

Could be yes. But it feels like MSFS for Windows 95.

1 Like
11

Don’t think so.
It seems High refresh is the old Medium…
I hope they fix this performance loss, it’s a reall pain to fly and see the HUD jumping around…

2 Likes
12

You mean the builtin planes, right?

ATR-72 cockpit isn’t limited to 30 FPS (not a builtin plane, and this is a plane not affected by this issue).

Anyway, I’ve edited FPS values in the original post now considering raw FPS in order to avoid confusion.

13

No, any aircraft using the Coherent framework, which can include default and third party planes.

14

I had mine set to “low” by default and immediately noticed how sluggish the avionics felt in the Longitude on takeoff compared to before.

I increased the setting to Medium and it feels better to me, though I don’t know what that setting was like before.

2 Likes
15

I am not experiencing this problem. Tried both in 2D and VR and my avionics are butter smooth. It was set to “High” and never changed them, so no issues so far.

1 Like
16

This doesn’t seem to be the case anymore. I closely inspected my video recordings, and it appears that at both the Medium and High settings, the avionics refresh every 3 frames. Tested on the Cessna 172.

17

What was your sim FPS during this test?

18

30 FPS, using V-Sync 50% on a 60Hz monitor. This is what I almost always use and the regression in glass display smoothness was very apparent.

Clean Community folder, and no modification to the stock content of any kind.

1 Like
20

I’ve just tested, and the avionics of the affected planes refresh at 20 FPS (raw framerate). If it was 30 FPS before, then it’s a regression. (simulator running at 60FPS)

Take a look (notice how the SVT is refreshing at 60 FPS most of the time (video recording may drop frames occasionally)):

I’ve spent some time making more tests, and the conclusion is the biggest performance hit in avionics happens when Frame Generation is ON.

I’ve edited the original post (again) with more details.

In short, avionics of affected planes behave like this:

FG ON now: ~11 FPS
FG ON before: 60 FPS

FG OFF now: 20 FPS
FG OFF before: 30 FPS

3 Likes
21

Well, at the instrument rendering layer, it isn’t even aware of frame generation. In fact, from a graphics stack perspective, most things aren’t, the FG just takes over after the whole frame is complete (with a little extra information from the engine) and creates synthetic frames in between the real ones based on pixel motion estimations (broadly).

However, the algorithm on the GPU has to guess as to what pixels are intended to be in motion or not. If I had to hazard a hypothesis, since FG actually adds load to the GPU and the pre-FG frame rate can come down, the avionics must just be under the frame rate required for FG to understand they aren’t static elements, and not generating enough motion to be smoothly interpolated anymore. This would explain how the apparent avionics FPS goes down with FG. As to the previous state, the avionics themselves weren’t ever 60fps at the source, they just were a high enough FPS for FG to pick up that it needs to interpolate those pixels and generate motion estimates.

In any case, we’re looking into the apparent regressions in some scenarios, as there is not intended to be any avionics frame rate differences from before, just better scheduling so all the screens don’t always end up on the same frame all the time.

7 Likes
22

Hope you guys can find the fix for this, my HUD is really choppy right now and makes it difficult to fly.
I’m in VR(5800X3D, 6800XT, Pico4)