100% CPU usage on particular windows PC in v11.1.0 and up

[philfontaine]

Describe the bug

The render thread is always at 100% CPU usage, even in Idle. This only happens on a windows PC at my work, and only happens on 11.1 and 11.2

11.0 works fine

Since this bug is probably not reproducible easily, I will include a dotTrace snapshot.

Turns out the dotTrace apps also use Avalonia v11.1 and therefore have the same bug (see screenshot below).

Let me know if there is anything else I can provide to help find the issue.

To Reproduce

• Create the most basic avalonia app using the default template
• Run the app

Expected behavior

The CPU usage is close to zero when the app is idle

Avalonia version

11.1, 11.2

OS

Windows

Additional context

AvaloniaApplication1 - [2024-11-18 20-54-13].zip

[philfontaine]

I'm also including screenshots and a snapshot for the same basic app but with v11.0.13

AvaloniaApplication1 - [2024-11-18 21-33-24] 11.0.13.dtt.zip

[maxkatz6]

Do you have any suspicious logs in the app? Or any exceptions, if you enable handling of all unhandled exceptions in debugger?
It could be a rendering device being lost after each frame, which would cause recreation of render target:

Avalonia/src/Avalonia.Base/Rendering/PlatformRenderInterfaceContextManager.cs

Lines 32 to 58 in 0774007

	if (_backend == null || _gpuContext?.Value.IsLost == true)
	{
	_backend?.Dispose();
	_backend = null;
	if (_gpuContext != null)
	{
	_gpuContext?.Dispose();
	_gpuContext = null;
	ContextDisposed?.Invoke();
	}
	if (_graphics != null)
	{
	if (_readyStateFeature?.UsesContexts != false)
	{
	if (_graphics.UsesSharedContext)
	_gpuContext =
	new OwnedDisposable<IPlatformGraphicsContext>(_graphics.GetSharedContext(), false);
	else
	_gpuContext = new OwnedDisposable<IPlatformGraphicsContext>(_graphics.CreateContext(), true);
	}
	}
	_backend = AvaloniaLocator.Current.GetRequiredService<IPlatformRenderInterface>()
	.CreateBackendContext(_gpuContext?.Value);
	ContextCreated?.Invoke(_backend);
	}

[philfontaine]

I ran the debugger, and nothing seems out of the ordinary (no exceptions or logs)

What I really believe is happening is that there is no pause whatsoever in the render loop, so the CPU is running at 100%.

I took another snapshot but with call counts, and it seems to confirm my theory since there are hundreds of thousands of calls in just a few seconds.

I also took a snapshot of the same app on v11.0.13 and the call counts are more reasonable (few hundreds)

AvaloniaApplication1 - [2024-11-19 08-40-54] v11.2 Call counts.dtp.zip