Sporadically Windows Desktop flashes through avalonia window

[msneijders]

Describe the bug
While fanatically scrolling the DataGrid example in the ControlCatalog.Desktop app (Release version, latest commit at writing this) I sporadically get my Windows Desktop flashing through. Looks like it is only one frame -- it does this maybe every 5/10 seconds.

I cannot reproduce this on my machine at work, this is on my home pc -- same Windows version -- so probably depending on GPU and drivers or things like that.

avalonia_desktop_flash.mp4

Screenshots
If applicable, add screenshots to help explain your problem.

Desktop (please complete the following information):

• OS: Windows 11, 10.0.22621
• NVIDIA GTX 2070, driver version 528.49

[ShawnMcCreight]

I get the exact same issue. Despite my best efforts, I cannot make it "not happen".

I am using the Render(...) and UpdateVisual(...) mechanism in a custom control.

[JerryJian]

Same issue too, especially some page with ProgressBars or anmiation elements.

[timunie]

any simple repo to reproduce would be very useful to analyze it further.

[Nypyren]

I also have this problem. It looks similar to when Youtube inside Chrome does the same type of flickering, so I investigated GPU settings and found one that SEEMS to work: Nvidia control panel -> Manage 3D settings -> Power management mode = "Prefer maximum performance" (was "Normal" during flickering).

My GPU is an RTX 3080 and I'm on Windows 10. Driver version is 537.13. My program is nothing but a grid of DrawingContext.DrawImage calls. Flickering only occurs when I am rapidly "scrolling" the grid. My source bitmap is NPOT, and I haven't tried a POT bitmap yet to see if that changes anything.

I suspect what's happening is the fluctuation in rendering activity when I scroll is just enough to switch the GPU's power modes and somehow causes a flicker during the switch. Just a guess though - I don't have any diagnostic info to back that idea up.

[ShawnMcCreight]

That works! I have a GeForceGTX 1070 on Windows 11. I changed the setting to "Power Management Mode -> Prefer maximum performance" and the flicker disappeared! The flick also happened during rapid scrolling. I have no idea why this would happen with Avalonia but not WPF on the same card, but I can tell you that I wasted a lot of energy trying to get it to stop. Thank you so much for your help!! Shawn

…

On Sun, Oct 29, 2023 at 4:20 PM Nypyren ***@***.***> wrote: I also have this problem. It looks similar to when Youtube does the same type of flickering, so I investigated GPU settings and found one that SEEMS to work: Nvidia control panel -> Manage 3D settings -> Power management mode = "Prefer maximum performance" (was "Normal" during flickering). My GPU is an RTX 3080 and I'm on Windows 10. My program is nothing but a grid of DrawingContext.DrawImage calls. Flickering only occurs when I am rapidly "scrolling" the grid. My source bitmap is NPOT, and I haven't tried a POT bitmap yet to see if that changes anything. I suspect what's happening is the fluctuation in rendering activity when I scroll is just enough to switch the GPU's power modes and somehow causes a flicker during the switch. Just a guess though - I don't have any diagnostic info to back that idea up. — Reply to this email directly, view it on GitHub <#10306 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AK5GW272DLPCFTICZRBQDYTYB3QCXAVCNFSM6AAAAAAUYVWVBWVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMYTOOBUGI3DGNZTHA> . You are receiving this because you commented.Message ID: ***@***.***>

-- Shawn McCreight ***@***.*** ***@***.***> 626-905-7623

[timunie]

Still a sample for us to reproduce and investigate the root cause would be useful. Probably SkiaSharp 3 can also help here. Update is not stable yet but we have a PR open to test it, if anyone wants to give it a try.

[maxkatz6]

If the same issue happens in the latest Chrome as well, it probably wasn't fixed in the latest Skia anyway. But SkiaSharp 3 might help anyway.

[ShawnMcCreight]

Ok. I have been messing around with garbage collection and I think I know what the problem is. In my code, I override the Render(DrawingContent) function to draw in a window. I wrap all the drawing operations inside another class which holds a pointer to the DrawingContent object for the duration of the call. This object expires at the end of the call BUT I think the garbage collector needs two passes to free the inner pointer to the DrawingContext. The result is that when there are a lot of drawing operations in rapid succession, there are a lot of DrawingContext objects that are uncollected. The simple solution is to null out the pointer to the DrawingContext before the function exits. Now the garbage collector will free the DrawingContext right away. I set the graphics card back to its factory settings and ran my program. Seems to be flicker free now.

…

On Mon, Oct 30, 2023 at 7:48 PM Max Katz ***@***.***> wrote: If the same issue happens in the latest Chrome as well, it probably wasn't fixed in the latest Skia anyway. But SkiaSharp 3 might help anyway. — Reply to this email directly, view it on GitHub <#10306 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AK5GW27PCZ5XXQJT4EWYE4DYCBRJFAVCNFSM6AAAAAAUYVWVBWVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMYTOOBWGM2TGMRQHE> . You are receiving this because you commented.Message ID: ***@***.***>

-- Shawn McCreight ***@***.*** ***@***.***> 626-905-7623

[StagPoint]

Still working on trying to produce a simple repro (it's been difficult to nail down), but for what it's worth I am experiencing the same issue where the window rendering spontaneously spazzes out and shows whatever is behind the window. I'm not doing any custom rendering (though that may not be true for all of the controls I use?) for whatever that's worth.

I'm on Windows 11 as well, with the following hardware:

And this is what the issue looks like (I'm using the Light theme, so anything dark is background):

[timunie]

could be related to Scottplot maybe? Also maybe a debugger issue. Maybe similar issue as #13589 ?