Please add an 'internal' sim frame rate limiter

Wish: I would like to please request that the ability to limit frame rate within in the sim itself, at the main thread level and independent of the VSync 20/30/60 fps settings, be added.

Reasoning: FSX had a very rudimentary main thread frame rate limiting config setting, limited to whole numbers, which worked independently of vertical sync and this had a number of advantages in that sim…

  • Very consistent frame times
  • Reduced cpu and gpu load in low density scenes
  • The sim seemed to “plan” out its threads more carefully with the limiter engaged, leading to much fewer stutters and microstutters from scenery loading etc

Why this is needed:

As MSFS is currently set up, when you are flying in VR, or with Vsync off in 2D, the only way to limit frame rate is to use an external limiter program (Rivatuner Statistics Server) or lock the frame rate at the videocard driver level. Neither of these methods is ideal, and they come with problems.

Example problem:

You are doing a loop in VR with frame rate locked to 30 fps in the video card driver. You’re looking at the ground to start, so the cpu and gpu loads are high. As your nose comes up the load on both drops dramatically as you suddenly only have sky and clouds being rendered. The sim does not know that its frame rate is being limited and keeps trying to push higher fps with the suddenly lighter load, and this results in a noticeable series of stutters as it basically trips over itself. It takes several frames for the driver’s limiter to smooth it back out again. As your nose comes down and the ground comes back into view again the same thing happens in reverse, with the cpu and gpu suddenly being heavily loaded again, and again the sim stutters severely as it tries to adjust to the new load. These are not scenery loading stutters, as you are barely moving laterally over the ground, they are purely caused by the sim being unable to predict and control its own frame times internally.

An internal frame rate limiter would help this situation tremendously if it is done correctly, so that each thread knows exactly how many milliseconds are available for its work, and if something is going to take longer than the time left in the frame it gets moved to the next one.

This would be an enormous help in VR, especially with motion reprojection / ASW active, which rely on having extremely consistent frame times. It would also be an enormous help in regular flying, as scenery loading stutters should be reduced if the sim actively truncates and segments tasks that would break the frame time limit.

Ideally this internal frame rate limiter should provide similar accuracy to Rivatuner Statistics Server, allowing for at least 1 or 2 decimal places of precision in either frames or milliseconds per frame (ie: 29.97 fps, or 33.34ms) etc and not just whole numbers. There are many cases where fine tuning of that precision is needed to remove microstutters (ie: most monitors refresh at around 59.94 fps, not 60).

Another side benefit would be controlling the runaway frame rate issues in the main menu in 2D, which currently can lead to extreme GPU load and temperatures, especially during sim updates, without the need to activate Vsync or use an external limiter. Perhaps a separate menu only frame rate limit could be added.

This limiter doesn’t need a fancy UI slider or anything, a simple config line setting in UserCfg.opt would be enough and most welcome.

Thank you for your time!

For Sim update 10, Asobo “said” they are going to add something to developer mode, get our feedback on it, then perhaps move it to normal mode if everything checks out. But will it be a proper FPS limiter? I really have my doubts.

I know I can limit my framerate in the nVidia CP. I don’t want to do that - I want to limit it in the sim. But the sim only allows three possible settings:

  1. 100% monitor refresh rate.
  2. 50% monitor refresh rate.
  3. 33% monitor refresh rate.

I want my monitor to be set at it’s highest refresh rate, with no limiting in the NVCP.

Can we have the ability of capping FPS in the sim with more granularity?

I have a 165MHz monitor. I’d like to be able to ‘dial’ my frame rate limit from, say, 30 fps to 165 fps, in much smaller steps, so I could dial in 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, etc.

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I agree… that’s the next step in tweaking …

Bizarre that this hasn’t been added yet. The in game options are only practical if you have a 60Hz display, which most people who also play other games do not these days.

For any practical usage there is no way for me to limit my FPS lower than 48FPS in the sim… might as well have no FPS limiter at all, completely useless.

And external limiters cause stutters…

Please address this in the very next update, I am sick of hearing about how great MSFS24 will be while the product we have bought has very basic design errors such as this with a huge impact to user experience… is this a finished product or did we pay full price for a MSFS24 beta test without access to the final product…

Played Modern Warfare briefly last night and noticed how well they’d implemented the framerate limit options…

image

If the image isn’t clear, that’s independent settings for Gameplay, Menus, and Out of Focus. Considering how long FS2020 takes to download and install updates, the last option of the three is particularly relevant.

I’m aware of the workarounds, but they shouldn’t be necessary.

If you are playing on an Nvidia GPU, this can be achieved by setting ‘Max Frame Rate’ within Nvidia Control Panel for the game/application!

I don’t know about whether this is possible with AMD, does anyone else know?