KDE On The Importance Of Wayland Explicit Sync

[rabcor]

"With the explicit sync protocol being implemented in compositors and very soon in Xwayland and the proprietary NVidia driver, all those problems will finally be a thing of the past, and the biggest remaining blocker for NVidia users to switch to Wayland will be gone."

Lol, the biggest remaining blocker for most sane people to switch to wayland, is that it only works sometimes, and usually not very well. (I am on wayland right now, I can say these things, and you can't say shit about me not knowing what i'm talking about, I've been using it for months, it sucks pretty bad even if you're decent at tinkering to make it suck less bad.)

This explicit sync thing, I mean really, it's 2024, why didn't we have this in 2008? Wait I think I remember, yeah it's coming back to me. 'Every frame is perfect'

[dec05eba]

With the 967 xwayland MR, this improves a lot.
But its still suggested to just run application as long as possible in native wayland, many sadly just launch with xwayland even thought wayland native works without any issues and dont have any flickering/backtracking at all.

But the 555 driver will be a great for all supported nvidia cards.

Unfortunately many wayland native applications crash a lot. I dont know if it's a nvidia driver issue or wayland support not being mature in those applications. For example firefox and vscode crashes every few minutes on my nvidia gpu when run in native wayland mode but has no crashes in xwayland.

[dragon321]

maybe read the below before writing 'NVIDIA' here or there:

https://www.collabora.com/news-and-blog/blog/2022/06/09/bridging-the-synchronization-gap-on-linux/

couple of quotes:

"The RADV driver currently tracks when each window-system buffer is acquired by the client and only enables implicit synchronization for window-system buffers and only when owned by the client. Thanks to details of the amdgpu kernel driver, enabling implicit synchronization doesn't actually cause the client to synchronize with itself when doing work on multiple queues."

"The end result is that we can't just rewire everything and drop in a new solution atomically. Whatever we do has to be something that can be rolled out one component at a time.

This solution allows us to roll out better explicit synchronization support to users seamlessly. Vulkan drivers seamlessly work with compositors which only understand implicit synchronizaiton and, if Wayland compositors pick up sufficient explicit synchronization support, we can transition to that once the compositors are ready"


The above is a post from 2022.
As you can see the plan is being actioned

... and AMD opensource stack has no problems with either implicit or explicit sync.

The fact it works doesn't mean there aren't any problems with it. As I said Vulkan is designed around explicit sync so if you want to support in on implicit sync stack you need various workarounds. Source you posted literally explains how it currently works and why it's not the best solution. For example this quote: "The important thing to understand is that there is no one strategy for dealing with this; every driver has its own. Also, all the strategies we've employed to date can cause massive over-synchronization somewhere. We need a better plan.".

Seriously there are good reasons why modern graphics stacks (including those based on Linux like Android) are not based on implicit sync concept. Why desktop Linux shouldn't follow them?

[Britoid]

the issue is because of nvidia

Vulkan relies on explicit sync, Android drivers use explicit sync and explicit sync matches up to the Wayland protocol much better.

Even though you could argue that Nvidia has forced this work by not supporting implicit sync, this is actually a scenario where everyone benefits and may have never happened otherwise.

[usta]

Unfortunately many wayland native applications crash a lot. I dont know if it's a nvidia driver issue or wayland support not being mature in those applications. For example firefox and vscode crashes every few minutes on my nvidia gpu when run in native wayland mode but has no crashes in xwayland.

to be honest i havent been hitting any crashes last 2 3 weeks.

image.png
Firefox 124.0.2 (64-bit)
Linux 6.8.4
Kde plasma 6.0.3
Qt 6.6.3
Nvidia 550.67
Cpu : i7 7700hq
Gpu : Nvidia 1050ti ( Mobile )
Manjaro Linux [ unstable repo ]

[jeisom]

maybe the keyword in your case is 'NVIDIA'

in my case the keyword is 'AMD opensource drivers'

anyhow I am happy for you that Plasma 6 works fine now

Obviously you can't read. I was referring to the AMD drivers on Plasma 5.27 being unstable and crashing all the time.

[Grinness]

The fact it works doesn't mean there aren't any problems with it. As I said Vulkan is designed around explicit sync so if you want to support in on implicit sync stack you need various workarounds. Source you posted literally explains how it currently works and why it's not the best solution. For example this quote: "The important thing to understand is that there is no one strategy for dealing with this; every driver has its own. Also, all the strategies we've employed to date can cause massive over-synchronization somewhere. We need a better plan.".

Seriously there are good reasons why modern graphics stacks (including those based on Linux like Android) are not based on implicit sync concept. Why desktop Linux shouldn't follow them?

it seems you can't read, or just can't understand English, try again:

https://www.collabora.com/news-and-blog/blog/2022/06/09/bridging-the-synchronization-gap-on-linux/

[mSparks]

The issue is because Linux relied on an outdated graphics rendering design (implicit sync) for 15 years longer than other desktop OS's.

....

Look up how old vista is and let that sink in.

ROFL,
making the linux desktop more like winblows isnt the improvement everyone is waiting for that you seem to think it is.

[Grinness]

Obviously you can't read. I was referring to the AMD drivers on Plasma 5.27 being unstable and crashing all the time.

Obviously you mentioned NVIDIA in your post, together with plasma 6 and x11 -- maybe you can't write

I use 2 different AMD GPU (Polaris and RDNA2) with wayland on 2 different systems since KDE plasma 5.26, no crashes -- maybe I am lucky

[mSparks]

https://www.collabora.com/news-and-blog/blog/2022/06/09/bridging-the-synchronization-gap-on-linux/

wow.....

This really is going to end badly for all involved....