Taskbar window caption shows [WARN: COPY MODE]

[badjames]

This appears on all WSLg window caption in the taskbar, but not on the actual window titles.

I have heard mentioned that this could be because WSLg is using RAIL rather than VAIL for the RDP transport.

I also noticed the following in the weston.log file which perhaps confirms that:

[10:40:49.922] WSL2_SHARED_MEMORY_MOUNT_POINT is not set.

In addition, "/mnt/shared_memory" is not present.

I am also getting quite poor 3D framerates despite having HW acceleration working (glxinfo shows renderer as "D3D12 (NVIDIA GTX 1070). Might this be due to the use of RAIL sending bits over the wire, rather than using shared memory as in VAIL? If so, how do I get VAIL working?

Update 18/06: I updated WSL (wsl --update) and this removed the "[WARN: COPY MODE]". However, OpenGL performance hasn't improved and I still don't see a /mnt/shared_memory.

[onomatopellan]

You need to upgrade to mesa 21.x

sudo add-apt-repository ppa:kisak/kisak-mesa
sudo apt-get update && sudo apt upgrade

[palapapa]

For those who thought that this didn't work, remember to run wsl --shutdown and then restart.

[biggestsonicfan]

Doesn't quite help for those not on a debian distro and who already have Mesa 23 or higher installed.

[RogerJL]

Works on Microsoft standard WSL distro
this fixes garbled qt graphics output (probably get window size wrong - clicking on widow helped but interactivity was lost)
Now this works, thanks!

[crystalfp]

Unfortunately not working.

And on console:

WARNING: dzn is not a conformant Vulkan implementation, testing use only.
WARNING: dzn is not a conformant Vulkan implementation, testing use only.
WARNING: Some incorrect rendering might occur because the selected Vulkan device (Microsoft Direct3D12 (NVIDIA Quadro T1000)) doesn't support base Zink requirements: feats.features.logicOp have_EXT_custom_border_color have_EXT_line_rasterization
glx: failed to create drisw screen
WARNING: dzn is not a conformant Vulkan implementation, testing use only.
WARNING: dzn is not a conformant Vulkan implementation, testing use only.
WARNING: dzn is not a conformant Vulkan implementation, testing use only.
WARNING: dzn is not a conformant Vulkan implementation, testing use only.
WARNING: Some incorrect rendering might occur because the selected Vulkan device (Microsoft Direct3D12 (NVIDIA Quadro T1000)) doesn't support base Zink requirements: feats.features.logicOp have_EXT_custom_border_color have_EXT_line_rasterization
glx: failed to create drisw screen

I run Ubuntu 22.04

[antonio-petricca]

Reappared after rebooting.

[spronovo]

This error message does indeed mean RDP is running in RAIL mode (copy pixels from Linux to Windows over the RDP transport) instead of VAIL mode (share memory between Linux and Windows).

This is actually independent of mesa or 3D acceleration / vGPU drivers. The WSLg shared memory uses virtio-fs which has been enabled in the WSL 2 Linux kernel from version 5.10.16+.

Could you verify the version of the Linux kernel you are running:

spronovo@OFFICE:~$ uname -r
5.10.16.3-microsoft-standard-WSL2

If you are running a version older than 5.10.16, shut down WSL wsl --shutdown and update wsl --update. If that doesn't pick up any update, double check that your .wslconfig isn't setup to use a private kernel (kernel=xyz) as this would load your private and skip any update we send down.

If you are on 5.10.16+ and you are still seeing that error, we would need to get the dmseg log from the Linux kernel boot session to see what failed when attempting to initialize virtio-fs. To gather this, you can enable the WSL debug console. In your c:\users\__user_name__\.wslconfig enter the following content:

[wsl2]
debugConsole = true

Restart wsl wsl --shutdown, and on restart you should see a console showing up each time you launch WSL and we boot the Linux kernel. Share the output you get there.

[badjames]

Thanks for the detailed response!

I was indeed able to resolve the issue via wsl --update

[garyo]

I'm having the same issue. WSL2, Ubuntu 20.04, uname -r reports 5.10.60.1-microsoft-standard-WSL2.
I recorded my startup debug log in this gist: https://gist.github.com/garyo/f386d9ee36729e58b72b098b2b07d51a
I do not have a /mnt/shared_memory in my distro.
My host CPU is AMD x86_64, Ryzen Threadripper 1950X 16-core.

Weirdly, it doesn't always happen. I see it on some apps always (emacs), some apps only sometimes.

[fredboulanger]

So at my end running 5.10.43.3-microsoft-standard-WSL2 on ARM surfacepro x. I get WARN:COPY caption on some apps, and for example vscode (installed in wsl2) doesn't. The issue with the apps showing warn:copy is they don't respond to window's window management (for example they don't snap) and they seem much slower.

Has anyone ran into this issue, and found a fix?

[spronovo]

Hi @fredboulanger, this is because on ARM platform our shared memory optimization aren't currently supported so WSLg runs in RAIL mode (copy pixels over the RDP channel). We have an updated WSL Linux Kernel for ARM in the pipeline that will be adding the missing support, after which this warning will be going away and your system will be running the more performant VAIL mode.

In term of window snapping, that's a known limitation at the moment as window movement and resize are handled on the Linux side of the world. This is something we would like to improve in a future.

[fredboulanger]

Thanks for the thorough response. Re window snapping. What I fail to understand if the lack of consistency between Linux applications. For context Firefox doesn't behave well but Spyder from Anaconda behaves like a Windows application. Maybe this is what you mean when you say it's a bug, the inconsistency between apps. Thanks again Fred Frederic Boulanger / 613.866 6997

…

________________________________ From: Steve Pronovost ***@***.***> Sent: Thursday, September 30, 2021 1:31:45 AM To: microsoft/wslg ***@***.***> Cc: fredboulanger ***@***.***>; Mention ***@***.***> Subject: Re: [microsoft/wslg] Taskbar window caption shows [WARN: COPY MODE] (Discussion #312) Hi @fredboulanger<https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Ffredboulanger&data=04%7C01%7C%7C257608279f5f4c9e3db308d983d397ef%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637685767080727141%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=9onH9CEXkMtlBrTdwYt%2FqQA0q%2FKGLaMKttBhGyselY4%3D&reserved=0>, this is because on ARM platform our shared memory optimization aren't currently supported so WSLg runs in RAIL mode (copy pixels over the RDP channel). We have an updated WSL Linux Kernel for ARM in the pipeline that will be adding the missing support, after which this warning will be going away and your system will be running the more performant VAIL mode. In term of window snapping, that's a known limitation at the moment as window movement and resize are handled on the Linux side of the world. This is something we would like to improve in a future. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub<https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fmicrosoft%2Fwslg%2Fdiscussions%2F312%23discussioncomment-1406901&data=04%7C01%7C%7C257608279f5f4c9e3db308d983d397ef%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637685767080727141%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=mdGpvySTz4BNSW%2BdMPojYC0GmuYFoGWWWW%2F%2FTkHxbSA%3D&reserved=0>, or unsubscribe<https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fnotifications%2Funsubscribe-auth%2FASKJIXWUSOBPDHNNCY6GNBLUEPY4BANCNFSM464CU4OA&data=04%7C01%7C%7C257608279f5f4c9e3db308d983d397ef%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637685767080737097%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=AQpUDL4ZE1GCW8ouFkY000DPv3CvJOCh7Hvo0PIzJbQ%3D&reserved=0>. Triage notifications on the go with GitHub Mobile for iOS<https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fapps.apple.com%2Fapp%2Fapple-store%2Fid1477376905%3Fct%3Dnotification-email%26mt%3D8%26pt%3D524675&data=04%7C01%7C%7C257608279f5f4c9e3db308d983d397ef%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637685767080747049%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=qQJREOhLgLzxy8oMc8T0SfQnBaFrqz5buQtIsziGV5c%3D&reserved=0> or Android<https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fplay.google.com%2Fstore%2Fapps%2Fdetails%3Fid%3Dcom.github.android%26referrer%3Dutm_campaign%253Dnotification-email%2526utm_medium%253Demail%2526utm_source%253Dgithub&data=04%7C01%7C%7C257608279f5f4c9e3db308d983d397ef%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637685767080747049%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=0LwmhehNs4oHl58cES7RULlyqL9QV6raOMBN%2F1udwSc%3D&reserved=0>.

[mitsos1os]

This was still valid for me and the solution proposed fixes the problem.

OS: Win 11 22H2
WSL2: Ubuntu 20.04.5
kernel: 5.15.79.1-microsoft-standard-WSL2

[ericblade]

I have been working on a custom distribution that i'm trying to get working in WSL, for the last several days, and everything was running fine -- and then suddenly it wasn't. WSL, as well as some windows processes, slowed to a crawl, and my 1 running WSLg process is showing [WARN: COPY MODE] on it. a wsl --shutdown hasn't cleared it, going to try rebooting windows.

Definitely is running mesa 24, using llvmpipe as the d3d12 drivers don't seem to like Apple's AMD cards.

update: rebooting fixed it. Suspecting some sort of resource leak inside my wsl distro, i attempted relaunching every single thing inside it again, which resulted in pulseaudio breaking instead of wslg, necessitating a wsl --shutdown to get back to anything working