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Ubuntu unveils its next-generation shell and display server

Ubuntu unveils its next-generation shell and display server

Posted Mar 7, 2013 2:52 UTC (Thu) by dlang (✭ supporter ✭, #313)
Parent article: Ubuntu unveils its next-generation shell and display server

> Høgsberg replied that Wayland could add support for that as well, noting "I realize that this all isn't really documented, but it's not like Wayland only works with client side allocated buffers."

when a project makes a big point about how it uses client side buffers, and then doesn't document that this isn't the only way it works, it's not surprising that other people assume that it is.

I hope that someone is gathering all the undocumented things that wayland can do (and how to do them) that were incorrectly assumed to be impossible and is adding them to the wayland documentation.

for a project that is so loud on the need to break compatibility, it seems 'wrong' that they would take such offense at someone else breaking compatibility. It may be that one group or the other is headed into a dead-end, but to take the attitude that only they should be allowed to break compatibility is the height of arrogance.


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Ubuntu unveils its next-generation shell and display server

Posted Mar 7, 2013 3:05 UTC (Thu) by airlied (subscriber, #9104) [Link]

insightful, -1.

Oh I forgot not the slashdot.

The thing is wayland isn't a hidden project, asking someone on irc or by email isn't hard. Making assumptions shows less character than challenging them. Try and find anywhere in the X11 documentation that explains how to write a window manager or compositing manager. That never stopped anyone from trying, much to our disdain in a lot of cases.

I don't think krh has ever said Mir shouldn't be allowed to exist, he has clearly stated that Mir shouldn't be bashing wayland in order to justify its existence, and that there may be no technical reason for Mir to exist apart from ignorance of wayland. Non-technical reasons for Mir's existence maybe also exist, that we are unaware of.

Ubuntu unveils its next-generation shell and display server

Posted Mar 7, 2013 4:19 UTC (Thu) by rsidd (subscriber, #2582) [Link]

The thing is wayland isn't a hidden project,
The thing is that wasn't the OP's point at all.

The thing is that wayland isn't an established project. It may not be hidden but, after five years, there is not a single product or distro that uses it or even has a timeline for when they will use it (correct me if I am wrong). Ubuntu wants to put something out in the next few months, and unify all their target devices by next year. Both projects are a break with X. Wayland should do a better job of explaining why they are the best way to do it, or else just let Mir be.

Yes, Mir made some incorrect claims about Wayland but those were corrected in less than a day. Are there any remaining examples of "bashing Wayland"? As a disinterested person (I use Ubuntu but not Unity), I don't think the Mir wiki "bashes" Wayland in any way.

Ubuntu unveils its next-generation shell and display server

Posted Mar 7, 2013 5:32 UTC (Thu) by raven667 (subscriber, #5198) [Link]

> It may not be hidden but, after five years, there is not a single product or distro that uses it or even has a timeline for when they will use it (correct me if I am wrong). Ubuntu wants to put something out in the next few months, and unify all their target devices by next year.

This is probably the biggest issue that has created Mir. There have been a few links to a post by Shuttleworth from two years ago which discusses a presumed shift to Wayland that indicated Canonical wanted to integrate it in the next 6mo cycle. That obviously didn't happen and Wayland didn't seem to stabilize on the schedule needed for Ubuntu integration. Maybe there just isn't enough resources behind Wayland, did Canonical have developers working on it or did they expect that others would do all the work without their resources? It seems that they would have been hot to integrate it if it was ready a year ago, which would have probably prevented this whole issue.

Ubuntu unveils its next-generation shell and display server

Posted Mar 7, 2013 6:59 UTC (Thu) by airlied (subscriber, #9104) [Link]

Canonical have never provided any resources to the wayland project. They have waited for some other distro to do the heavy lifting, you have to also remember the wayland devs have not just been working on wayland for the past 5 years.

Most of krh's time has been spent getting the mesa gbm/egl layers to a place where wayland is actually possible, and open source stack supports it.

If someone had come along a year ago with a direction for wayland and 4-5 developers there would have been very little to stop them taking the project in whatever direction they wished. You'd at least talk to the upstream project first, to see what benefit you could gain from it.

There's a pretty good chance Fedora 20/21 will see some movement in waylands direction. But if Canonical had put the effort into wayland instead of Mir we might have had a reason to help out earlier and assign resources.

Ubuntu unveils its next-generation shell and display server

Posted Mar 7, 2013 14:02 UTC (Thu) by dbnichol (subscriber, #39622) [Link]

Writing a display server from scratch somehow accelerates their product? That doesn't make any sense at all. Not to mention that they're now doing this completely on their own now and will receive no help from the open source graphics veterans working on Wayland now like Kristian and Daniel Stone. People that have been doing this for years and have a pretty good idea of what a display server (X) should and shouldn't be doing.

If time to market was all they cared about, why not use X? Or why not just fork Wayland/Weston since that code already exists? Or just use SurfaceFlinger? I don't think time to market makes sense as the driver for Mir. It seems a lot more about control.

Ubuntu unveils its next-generation shell and display server

Posted Mar 7, 2013 17:05 UTC (Thu) by raven667 (subscriber, #5198) [Link]

> Writing a display server from scratch somehow accelerates their product?

Not having to integrate or coordinate with anyone else accelerates development, just as Fred Brooks 8-)

> People that have been doing this for years and have a pretty good idea of what a display server (X) should and shouldn't be doing.

They might be able to get something lightweight that works 90% for their one use case without worrying too much about the corner cases, it's the last 10% to make it robust and complete where the difficult work is. This reminds me of mjg59's criticism of LightDM, by the time you've solved the real-world problems and discovered all the underlying requirements your "lightweight" system has just as much complexity as the "crufty" thing it was meant to replace.

So I think they can ship something that pretty much works, but it'll take years to get to the same place that Wayland is today, just like Wayland took years to build, and then they'll have another big of private infrastructure to maintain that takes away time from actually adding value to what they are selling.

Ubuntu unveils its next-generation shell and display server

Posted Mar 8, 2013 13:56 UTC (Fri) by robclark (subscriber, #74945) [Link]

> Not having to integrate or coordinate with anyone else accelerates development, just as Fred Brooks 8-)

well, maybe for whipping together a prototype.. for getting something that handles all cases (multi-display, hotplug, various different apps, etc) it is not. In the end we just end up with something that works ok in simple cases but is not as mature/robust as wayland, and everyone loses.

Ubuntu unveils its next-generation shell and display server

Posted Mar 7, 2013 11:59 UTC (Thu) by ewan (subscriber, #5533) [Link]

"Yes, Mir made some incorrect claims about Wayland but those were corrected in less than a day."

You say that as if it's somehow a good thing - the problem is that Mir exists (ostensibly) because of technical misunderstandings that could have been cleared up in less than a day months ago. Canonical devs just didn't even bother to try - that's the problem.

Ubuntu unveils its next-generation shell and display server

Posted Mar 7, 2013 4:30 UTC (Thu) by hoegsberg (guest, #57768) [Link]

I think perhaps you're confusing client side decorations for client side allocated buffers? Client side decorations come up again and again, but we've never really talked much about client side buffer allocation.

Client side buffer allocation refers to how the client allocates its own pixel buffers directly from the kernel memory manager instead of going through the server. It's an implementation detail in the mesa side of Wayland and it's not something we ever really made a big point about. It's all covered by the wl_drm interface, which is private to mesa, defined in mesa and not part of core wayland. Other driver stacks would define their own wl_$chipset interface and allocate and exchange buffers whereever and however they want/need to.

And it's not a matter of "Wayland adding support" for server side buffers. It's not a feature in itself, it typically means that your hw or driver has restrictions on which process can allocate memory. The misconception here was that because the mesa integration code allocates buffer client side, other drivers wouldn't be able to allocate through the server.

Ubuntu unveils its next-generation shell and display server

Posted Mar 7, 2013 10:10 UTC (Thu) by dgm (subscriber, #49227) [Link]

>for a project that is so loud on the need to break compatibility

Wayland is not X11, and so it needs not be compatible in any way. Yet, X11 applications run just fine under Wayland (by means of XWayland).

How can you possibly call this behavior "being loud about breaking compatibility"? In any case, it's just the opposite!

Ubuntu unveils its next-generation shell and display server

Posted Mar 7, 2013 11:03 UTC (Thu) by hummassa (subscriber, #307) [Link]

Honest questions:

* is XWayland already working?

* is Qt/Wayland working?

* is Kdelibs/Qt/Wayland working?

To the other side:

* is Qt/Mir already working?

* is Kdelibs/Qt/Mir working?

Ubuntu unveils its next-generation shell and display server

Posted Mar 7, 2013 11:47 UTC (Thu) by ebassi (subscriber, #54855) [Link]

> * is XWayland already working?

yes

> * is Qt/Wayland working?

yes

I'll also throw in GTK and Clutter to the list of toolkits working under Wayland.

there are bugs? sure. are they being fixed? yes.

Ubuntu unveils its next-generation shell and display server

Posted Mar 7, 2013 19:23 UTC (Thu) by Serge (guest, #84957) [Link]

> Honest questions:

Don't ask people that like wayland — they will say you that it works. Don't ask people that hate wayland — they will tell you that it's not. Download livecd and try it yourself: http://sourceforge.net/projects/rebeccablackos/

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