CPU usage 100% in Linux (ubuntu 20.04)

[sakya]

CPU usage 100% in Linux (ubuntu 20.04)
The project XamlControlsGallery under Ubuntu 20.04 and using Avalonia 0.10.0-rc1 has a CPU usage of 100%

To Reproduce
Steps to reproduce the behavior:

1. Download the XamlControlsGallery source code
2. Update reference to Avalonia 0.10.0-rc1
3. Run

Expected behavior
The app shouldn't use 100% of CPU

Screenshots

Desktop:

• OS: Linux Ubuntu 20.04
• Version 0.10.0-rc1

[danwalmsley]

Does your system have a gpu or is it relying on software rendering?

[sakya]

I'm using a GeForce GTX 760M (Xorg)

[sakya]

Driver version
NVIDIA-SMI 450.80.02 Driver Version: 450.80.02 CUDA Version: 11.0

[devel0]

I experienced same problem using 0.10.0-preview5 and nvidia gtx 1050ti but using latest 0.10.0-rc1 problem solved.

Seen now that sakya already used 0.10.0-rc1, please try to cleanup bin and obj rm -fr obj bin and try to rebuilt just to ensure you using rc1 version. If problem still there may related to other parts of avalonia involved by your project that doesn't repro with my case. Other thing to try is to upgrade dotnet to net5.0

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net5.0</TargetFramework>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Avalonia.Desktop" Version="0.10.0-rc1" />
  </ItemGroup>

</Project>

or try with older version such as 0.10.0-preview2 to verify if exists other version that doesn't cause the problem.

[sakya]

Hi, I cleaned the build, changed to net5.0 but the cpu is always 100%
This seems really related to Linux because the same project run on Windows on a Celeron J1900 with Intel integrated graphics uses 2/5% of CPU.

XamlControlsGallery-master.zip

[devel0]

Thanks, It's ok its related to known bug ( #2012 ) if you comment out this cpu goes ok

      <!-- <ProgressBar IsIndeterminate="True" Margin="0 40" /> -->

btw for my project where I not used progress bar I had that problem of cpu when using the previous 0.10.0-preview5 while 0.10.0-rc1 solve, so seems there are some progress fixating the issue of high cpu usage on x11 excluding in fact the progressbar when indeterminate mode.

[sakya]

You're right, many thanks!
I had this problem with a different project. In my project I don't have any indeterminate progress bar but I was able to fix the issue.
I have a spinner with an animation set to INFINITE. The spinner is shown or hidden...well when it's hidden it seems that the animation runs and uses 100% of the CPU.
I solved the issue by stopping and starting the animation when i show/hide the spinner.
So it seems that on Linux animations run even on hidden elements, while on Windows not?

EDIT: or are animations just a lot heavier on Linux?

[kekekeks]

CPU usage is probably caused by triggering the render timer more frequently. Everything else should be the same for all platforms.

[sakya]

Ok, many thanks for the help!