bug: Vulkan has frame pacing/consistency issues on Windows

[swarnimarun]

Bevy version

0.15.3

Relevant system information

Nvidia GPU, Wgpu with Backend Vulkan

What you did

Simple platformer 2d game with basic input and updates has very weird frame pacing and input latency issues.

What went wrong

The issue appears to be some form of bad Vsync, I haven't had time to debug it, but adjusting to DX12, setting Window PresentMode to AutoNoVsync, and using the framepace plugin all fix it.

I understand why AutoNoVsync and Framepace work, but DX12 having different or in this case correct behavior is weird to me.

I was expecting if it's a bad behaviour it should be same with all backends.

Additional information

Don't have a good illustration, video doesn't quite do the issue justice, as there is no tearing or visual artifacts but rather artifacts related to inputs.

But to repro default setup of bevy on windows should do the trick, it might be Nvidia specific, I haven't tried my AMD setup yet.

Suggestions

I think making the behaviour consistent should be priority, as it's very unexpected to see such massive difference between the two. Could also be a wgpu or winit issue as well, though why it happens specifically with Vulkan (DX12 works fine) is something worth looking into.

[IceSentry]

This is a wgpu issue, we don't do anything that is backend specific. If a backend behaves differently to other backends then it's on wgpu.

[janhohenheim]

I have a friend that got this issue exactly when having Firefox open. Does your issue also get fixed by closing other windows?