Micro stutters in glass cockpits (+ simple benchmark analysis included)

[Ohmsquare]

Flying a glass cockpit aircraft produces micro stutters, not perceivable when flying a steam gauge A/C. The experience in glass cockpits is definitely less smooth and enjoyable.

So I did a simple quick benchmark testing two aircraft spawned at the same place in identical conditions. PC specs and performance settings are below. No custom mods active.

By micro stutters, I don’t mean the occasional spikes present near heavy densed scenery. I perceive micro stuttering as fairly constant jerky movement impacting overall smoothness.

The results:

DA40 NG, avionics ON (Garmin 1000), HIGH GC refresh rate: Main thread Limited@15-16 ms, micro stutters present

DA40 NG, avionics ON (Garmin 1000), MEDIUM GC refresh rate: Main thread Limited@~14 ms, smoother, but noticable micro stutters still present

DA40 NG, avionics OFF: Main thread Limited@~14 ms, micro stutters perceived, but overall much smoother experience than those above

DA40 TDI, avionics ON (Garmin 430): Main thread Limited or GPU limited@~12 ms (however mostly GPU limited), no micro stutters perceived, generaly very smooth

DA40 TDI, avionics OFF: GPU limited@12 ms, perfectly smooth

Graphics settings (high/ultra, level of detail@100, 1440p):

Summary

Traffic settings:

Summary

Data settings:

Summary

NVIDIA settings:
All driver default
Fixed refresh rate (144 Hz)

Windows:
20H2, 19042.746
Graphics performance preference: ON
Game mode: ON

PC spec:
CPU: Ryzen 3600
RAM: 16 GB of RAM@3200, 16:18:18:36:56
GPU: Nvidia 3800 (slightly undervolted, power limit@90%)
Drive: NVMe

[UP1952HU]

I don’t quite understand that. Did it happen that you changed the graphics settings to such an extent that you reached the GPU limit? So you raised the level of your graphics settings?

[sneaky74]

Hi @UP1952HU you can see the GPU budget in the Asobo performnce monitor and it’s fine. All the graphs are in the green for the most part so this isn’t taxing the GPU or CPU 99% of the time.

The microstutters are caused by small delays in the rendering pipeline held up by the CPU process to compute the EFIS graphical display information (Garmin display). I had the same issue with some third party maps I added to the sim.

The FlyByWire team were able to get much better smoother performance for there A320 mod by changing the way EFIS displays were updating by only updating part of the display at a time which resulted in a much smoother flying experience. Hopefully that’s something Asobo adopt with the default planes going forward.

[UP1952HU]

Thank You. So the point is, until the program is improved, we have to live with it.