from cyberwolfie@lemmy.ml to linux@lemmy.ml on 09 Jul 2024 10:25
https://lemmy.ml/post/17789505
I switched to Linux about 1.5 years ago now when replacing my old Macbook Pro with a Tuxedo Infinity Book. I am super happy with the transition, and for the most part my digital life has severely improved as a result of it. There’s one thing in particular though that I haven’t fully grasped or understood despite all the talk about it, and that really has mostly caused confusion on my part, and that is Xorg/X11 (I don’t know the difference…) vs. Wayland.
I started out with Tuxedo OS 1 and 2 running KDE Plasma 5.x.x, and thus have been on X11 for the most part since switching to Linux. I never dared switching to Wayland myself. However, they somewhat recently started offering optional upgrades to Tuxedo OS 3 running KDE Plasma 6 where Wayland is the default, and I took the plunge. The only real difference I noticed was small annoyances that I had to fix. Glitching windows running on XWayland and having to configure some .desktop
-files to force apps to launch natively in Wayland. Apps not showing the correct desktop icons but the generic Wayland logo instead, making Alt+Tabbing a bit more difficult because it is harder to tell applications apart. Annoying smooth scrolling (I don’t want scrolling to have as much friction as polished ice) activated in all kinds of applications that I seem to have to turn off individually. Nothing breaking (though I haven’t dared booting with my Nvidia dGPU yet in fear of breaking something irreversibly…), but I haven’t noticed any improvements either, and I find it a bit frustrating not knowing where to make the necessary changes and always having to search for it seemingly on a case by case basis.
Now for instance I was updating FreeTube to a new version, and the flags I previously added to the ́.desktop’-file suddenly doesn’t work anymore (–enable-features=UseOzonePlatform,WaylandWindowDecorations --ozone-platform-hint=auto
). The application won’t launch unless I remove them, but then it launches under XWayland instead. Not that I have any issues so far running it like that, but I guess I would prefer to run everything natively in Wayland if I can.
threaded - newest
Wayland should be faster. What would you expect to happen? It should just work, while in the background EVERYTHING is changing.
For Freetube, it should automatically detect running on Wayland and use that. But I had one bug on Freetube only on Wayland, may be an Electron issue.
I had assumed that I would get a somehow smoother experience (such as speed, for instance) or some other perceivable benefit, but I think Ramin Honary nicely highlighted the necessity of the change on the backend side. So your point is good, maybe I should just expect a smooth transition where I don’t notice anything.
If I run the executable after downloading from the GitHub repo directly, it launches in XWayland. The additional parameters I mentioned in the post used to work to launch it in Wayland, but not anymore.
Yeah I am referring to Freetube Flatpak, where a script is launching the binary, that detects Wayland and uses the boot parameter then.
github.com/flathub/…/run.sh
I can explain the difference between X11 and Xorg with an analogy to the web and web browsers: X11 is like HTTP, Xorg is like the Chrome browser. X11 is the protocol, Xorg is software that implements that protocol.
X11 is old, it was designed back in the 1980s and includes messages for drawing lines and circles and fonts on the screen. Also, back then there were a lot of “thin clients”, computers that were basically nothing but a browser, since graphics were computationally expensive and could not be done on the client computer, graphics rendering was done server side. There are lots of messages in the protocol for handling screen updates over a computer network.
Nowadays, all personal computers are powerful enough to render their own graphics, and no one needs the display server to draw individual lines or circles on screen. Vector graphics and fonts are done at the application level, not over the network. So these these messages specified in the X11 protocol are hardly ever used. Really, most of X11 (let’s say 90% of it) is not used at all, only the parts where the keyboard and mouse are defined, and how you can allocate memory to buffer a graphic and copy that buffer to the display. But you still need to maintain the Xorg software to handle everything that X11 specifies, and this is just a waste of code, and a waste of time for the code maintainers.
So basically, they decided about 10-15 years ago that since no one uses most of X11, let’s just define a new protocol (called Wayland) that only has the parts of X11 that everyone still uses, and get rid of the 90% of it that no one ever uses. Also, the protocol design takes into account the fact that most modern computers do all of their own rendering rather than calling out to a server to render for them. Also the Wayland protocol design takes into account that a lot of computers have graphics cards for accelerated graphics rendering.
Since the Wayland protocol is much simpler, it is easier for anyone to write their own software which implements the protocol, these software are called “compositors.” Finally, 10 years after some of the first implementations of Wayland, the protocol and compositors are becoming mature enough that they can be used in ordinary consumer PCs.
Thanks for such a detailed account - it really makes sense to move on from X11 based on what you write.
When I first heard about what X11 and Wayland was and how long the transition has been in the making, I found it a bit hard to believe that it should take so long. I am still not fully sure why it would take so long time to mature… is it a chicken-and-egg kind of situation where it cannot mature properly before it is more widely used, but it has not been more widely used because it was not mature enough? Or is it such a difficult task to get this right and that the development time reflects that?
And why would for instance NVIDIA GPUs continue to have issues with Wayland (and what kind of issues would actually be caused by this?)? Is that a matter of closed source drivers and lack of support from NVIDIA’s side to implement required changes? Or are such issues on a more fundamental level (i.e. architectural differences that somehow factors into this - I have no idea what I’m talking about now, I’ll stop writing…)?
Re: maturity - I think it is the latter where the problem is very complex and the dev time reflects that, it takes a long time to implement all the features people need and are used to in X11 (or, used to when coming from windows/macOS). For instance, screensharing is still not widely solved across all wayland compositors. In Gnome or KDE Plasma, it works as you’d expect. But a smaller project like river (tiling window manager that I daily drive rn) does not handle screensharing out of the box and takes some extra configuration - and even then it’s got some oddities that I didnt have in KDE.
As for your issues with NVIDIA gpus under Wayland, yes I think it comes down to driver support from NVIDIA (or the open source drivers just need to mature some more)
Closed source drivers are not really the issue. But competing graphics APIs are. With the move to Wayland open graphics drivers were updated to support the GBM graphics API which if one window manager wants to support then it gains support for all graphics drivers that use that api. But nvidia created its own api, eglstreams that to support required all window managers to write extra code for. Some refused to do that or took a long time to do.which gave shoddy nvidia support.
Some did support nvidia slowly, but then nvidia also switched to support the same api as everyone else (poorly at first but I assume it has improved over the years). Nvidia have also partly released their drivers as open source which has also helped.
Ah, OK. I wasn’t aware of those APIs, only things like OpenGL and Vulkan, but those are perhaps specific to 3D graphics rendering?
And windows managers in the context of Wayland are the same as Wayland compositors? Which compositor would I be using through KDE Plasma 6?
KDE uses KWin by default, which can do both X11 and Wayland currently.
Don’t forget Wayland and security into the mix as well. That seems to have caused some of the biggest issues with apps. Don’t get me wrong though, security was desperately needed. X11 had no concept of security.
Do you mean that Wayland has had its own security issues, or that enhanced security has caused additional issues for apps to run correctly?
My understanding is that due to X11’s design, all running GUI apps can “see” all the other apps. If you’re running a malicious program in X11, it can easily snoop what else you are doing, log your keystrokes, etc.
Wayland solves this through better design.
The addition of security has caused issues.
E.g. apps not being able to see other apps by default has caused issues for some screen recorders or screen-sharing software. Or screen readers from seeing inside apps.
Or apps not being able to see keystrokes when the app isn’t active, impacting global shortcuts (say, for example, you’re a streamer who uses a hotkey to change cameras in OBS)
A lot of Linux stuff was written with the expectation of there being zero security safeguards. With Wayland, that has changed and it’s causing issues.
The second one. Some apps were taking advantage of the fact that X allowed any program access to EVERYTHING on your screen, shortcuts, etc. Wayland ensures more control, which is excellent news, but definitely the change requires programs to adapt, and some have not (AnyDesk, for example).
It was created in a time when physical restrictions on access to the machine was enough. If you weren't meant to be in the lab, somebody found out real quick.
Wasn't just that, it was everything. DOS, early Windows, etc all didn't give a rat's ass about security. In 1986 you could just go over to your friends house and turn on their machine and just go through all their shit laid bare. I don't even think we had BIOS passwords at the time. At least the machines I used didn't. It was a wild time.
.
The biggest benefits of Wayland over Xorg are to the developers maintaining it, not to the end user.
The Xorg project has become difficult to modify for new features and fixes and so they’ve decided to rewrite it.
As a result users will eventually see some benefits as Wayland implements features that were difficult to do in Xorg over time. But in the meantime it’s causing everything to be rewritten to support the new standard. And it’s a pain in the ass.
If your application works as you want on Xwayland there’s no reason to try to get it to work on Wayland native. Xwayland won’t be going away anytime soon. Eventually those applications will just switch over to Wayland and you shouldn’t need to think about it.
My department is rewriting a lot of its codebase, and we only have 15yrs to deal with vs Xorg’s 20. Pain in the ass, indeed.
It’s not something that you can really experience directly as the end user. It’s a base on which other features can be built. Most obvious would be fractional scaling.
So, I’m going for a long explanation just in case, just skip the parts you already know.
tl;dr: Wayland is more modern and potentially better, but development on the linux desktop is slow so some parts are not ready yet. You should use it for future-proofing, unless there is some X11 feature that you really really need. But you probably won’t notice much on the surface. Check your drivers/desktop environment versions if you have flickers on nvidia, you need the very latest versions because of a recently resolved issue.
Backstory:
Xorg is a program, X11 is the protocol used by said program. Xorg is old, insecure, inefficient, it is based on an idea of how graphics work that is outdated and doesn’t reflect modern hardware. But most of all, its code is a mess, and it is impossible to update it to fix those issue. Thus, the Wayland protocol was born as clean-slate replacement, meant to solve some issue (make it more secure), clean up the software (Xorg is unmaintainable), and make it reflect the way modern graphics work (less intermediary, no network transparency, no per-vendor implementation), but as a consequence, it breaks compatibility with old software.
Also the developer of xorg were so traumatized by x11 that when making Wayland they went to much in the opposite direction and were reluctant to implement some features, most of which have now been added as protocol extensions or separate software, but some are considered against the protocol design principles and will never be implemented. One of the differences is that there’s no standalone display server, but you have a window manager+compositor+display manager, so Desktop environments need to make their own or support the one made for other environments, that’s why only a few of the long-standing DE support wayland, for now.
What makes Wayland good (plus drawbacks):
Less intermediaries mean theoretically more efficiency, thus speed. Of course, that is only true if the compositor is mature enough, after all X11 software is very mature.
In ye olden times every vendor provided a closed source implementation of the x11 protocol, and that’s how drivers worked. That is objectively a bad idea, so during the years glamor was developed, to run Xorg directly on OpenGL instead of on an ad hoc driver (put a pin on this for later). In Wayland you don’t need ad hoc drivers, they just need to provide Egl (not to be confused with EglStreams) and a library called GBM, that are used for managing frame buffers.
Xorg used to manage a huge part of the devices (even printers…), and due to antiquate design, it was unable to handle trackpads correctly (e.g. no proper kinetic scrolling), Wayland does less, and relies on other more modern input management libraries, this theoretically allows input devices to work better, but only if the related new libraries and protocols are ready. E.g. he trackpad part is ready, the drawing tablet part is not.
It is more secure, for example it doesn’t allow programs to just read the screen. It is absolutely possible to do screen recording, but you need modern software, and some applications (e.g. discord) are really reluctant to update their libraries (discord is using electron from 2018), so they don’t get recording. A problem is that it doesn’t allow applications to move windows, some protocols are being worked on, but right now, software that relies on moving or placing windows will not work.
Applications (plus possible work around for freetube):
Most applications using modern libraries and toolkit don’t need to care about Wayland support, the toolkit will do the job. They might be undertested on Wayland tho, and small projects might not have the resources to test and take care of both protocols, so they will choose X11 because it’s still the most used.
Most older applications also don’t need to care, because Xwayland works just fine (put another pin on this), but sometimes they are a bit broken. And if they are specifically tools for xorg (e.g. xscreensaver) they will of course not work.
Some times electron apps still have issues, because chrome has not had proper Wayland support for a long time. More over, Google does make a version of chrome with improved Wayland compatibility, but they ship it with chromeos. You might fix some issue by adding
–disable-gpu
which disables electron’s gpu support.Expect proprietary applications to not fully support native Wayland, because their vendor often don’t care.
Java applications don’t support native Wayland because AWT is fundamentally incompatible with Wayland. JetBrains is working on a replacement.
Nvidia, Xwayland, and Glamor (this probably concerns you):
Recall the pins from before.
Nvidia provides it’s own proprietary implementation of X11, like in ye olden days. When they decided to support Wayland they decided that they wanted
Thanks for taking the time writing this up, it is very helpful for my understanding (and I imagine many others’ as well)! For the things I don’t completely understand for now, this also gives me a lot of additional pointers for what to learn more about to get a better grasp. So it goes straight into my notes for future reference.
Sounds like I should dare to activate my dGPU and reboot to check it out now then :) My biggest worry was that it would be so severely broken that I wouldn’t be able to switch back, but I know that is just an irrational fear - no way Tuxedo would’ve switched to Wayland by default if it broke their own laptops. But I’ve been a little twitchy about larger updates since I deleted KDE accidentally from not properly reading/understanding the prompts during update.
Well in the worst case you can always enter a tty or ssh and try to fix from there. But you can be sure the system will be recoverable.
I took a simplistic approach on some of the things I talked about, but you can use it as a pointer for a deeper dive. Also I realized now that I wrote the comment in really bad English, apologies.
I really do believe the future of the Linux desktop will be exciting, and that’s also thanks to Wayland.
I’ve never heard of AWT being incompatible with Wayland, I’d love to read more on that if you have any!
I saw it on a blogpost somewhere about jetbrains working on Wayland support for Java, but it was a long time ago, I don’t think I can find it. This has the gists of it blog.jetbrains.com/platform/…/wayland-support/
You already understand. Wayland isn’t there yet.
This so much, also aside from being modern I don’t see much benefit from architectural side.
I can name one improvement: global scaling works SO much better in Wayland
But obviously if you don’t have a high DPI monitor, this won’t matter to you
At the very beginning in early 90’s Linux adopted X11 implementation that was XFree86. It was obvious and pragmatic move, because Linux was UNIX clone with full POSIX standard compatibility, and X11 was already there for almost a decade. Porting it allowed for having graphical interface very early on (Linux started in 1991, X11 support was added one year later) and allowed all the contemporary UNIX software to be easily ported to Linux.
X11 however was designed with completely different needs in mind, as UNIX machines were mostly mainframes or powerful workstations and not home computers. It was about a lot of features that make no sense in this day and age (like network transparency, drawing primitives, printing capabilities, font rendering etc) and its design aged like milk. Xorg (that was fork of XFree86 started after license change) was implemented in a way that allows keeping compatibility for the time being with many issues being worked around and the old solution being effectively forcefully framed into modern use. It’s basically huge
Wayland started as an idea on how to do graphics on Linux (and other UNIX systems) without X, but it was never meant to be drop-in replacement. That being said, it’s vastly incompatible and the shape towards having Wayland desktops is long process of gradual implementation of new protocols to make it complete eventually.
Making Wayland possible took redesign of the OS itself. In old days, Linux didn’t think much about graphics and it was the monolithic X server that took responsibility of things like loading video drivers, setting screen modes or pushing stuff to video memory. Wayland was all about split of X’s features outside of X to gradually remove the dependency, so now the kernel has native system interfaces like kernel mode setting, direct rendering manager and so on. It’s not only Wayland taking advantage of it, as the same infrastructure is now used under X too.
Your experience wasn’t much different because it wasn’t meant to be. Desktops that are ported to Wayland are very good at abstracting things that are specific to both (otherwise completely different) display systems. You can gradually find about some things being different over time as you dive deeper.
There are certain limitations of X that Wayland doesn’t have:
On the other hand, X is very open to the user and applications, providing all sorts of information about opened windows and sniffing input globally by any client (focused or not) is a feature. In 1984 no one really thought cybersecurity will be important factor. So on Wayland:
For those and other reasons (like availability of desktop environments and window managers), some still prefer Xserver.