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Comment Re:I guess they realised... (Score 1) 138

I disagree. Wayland is essentially a subset of what X11 can do. It is based on sending messages over a unix domain socket and sharing buffers. This is exactly what modern X clients also do. This is no surprise: It was designed to support exactly what is needed for modern clients and no more with the explicit goal to get rid of everything else. But it does not add anything which you cannot also do in basically the same way with X.

Trying to say that just because it uses sockets makes it like X11 doesn't make it so.

This is true. This is about retaining backwards compatibility.

Right... so we must maintain backwards compatibility for barely used functionality even when it impacts on performance in the every day use case. And even when you can have backwards compatibility by running Xwayland or by running X11 without Wayland while everyone else enjoys a better experience.

Extensions are nice way to make modern rendering possible without breaking backwards possibility. "fool" "2D-centric" "1980" is just FUD to make it sound bad, but X supports modern applications just fine. You have no technical argument.

It's not FUD, it's true. X11 is from an age where the screen screen was a bitmap and every window to be a region in that bitmap. When you moved one window over another the server would throw out damage events and every client would repaint their areas. And x, y coordinates for mouse moves were simple transforms from screen to window coords.

This model is totally discordant with a modern compositing desktop. X11 has gained a compositor extension which is hacked into this model but underneath it still thinks the same way. So the compositor must duplicate state from X11 except sometimes windows might be scaling or otherwise not where X11 thinks they are. So all the x, y mouse coords are screwed up and don't map properly. Oh and because the compositor is a separate process it means extra context switches in and out of the damage event so the server can preserve its worldview.

In Wayland the compositor, server and window manager are the same process. So the state isn't duplicated or mismatched and compositing does not require a context switch.

Because modern clients work essentially in the same way on X as on Wayland,nothing is slower or less efficient. Just because some API is based on an extension or not doesn't make it faster or slower. This is simply FUD.

Wrong. X11 incurs more context switches than Wayland to recomposite or to handle input messages. There is a simple diagram that demonstrates this point.

No. Mostly, it will break backwards compatibility, and remove features. The few kilobytes on unused drawing API in X11 will not make any noticable different on desktops (or mobiles) with gigabytes of ram.

Run X11 over Wayland if you want backwards compatibility or start the desktop with the X11 backend. There's no reason your esoteric needs should impact on the experience everyone else suffers from. And thankfully that reality will soon be realized.

Comment Re:And this is what that means: (Score 1) 289

Has adblock "won". I think it's better to say its winning, but the more people use it the more likely that sites will develop effective countermeasures.

It would be relatively straightforward to circumvent adblock. All it requires is that the ads be delivered from the same domain for urls used to fetch the content and ads cannot be separated by pattern matching. This might be too much effort for some smaller websites but I see no reason that bigger sites couldn't do it. e.g. 3rd party advertisers could offer some kind of webapp that runs inside the host's DMZ and works in conjunction with some kind of frontend url resolver that sends requests one way to fetch content or the other for ads (and ad clicks) so they both appear to originate from the same host.

It would also be simple to block the adblockers by looking for page elements which should be there but aren't and blocking the user until they disable ad blocking on the site. Some sites already do this and more might do it in time.

Comment Re:I guess they realised... (Score 1) 138

The Wayland API is nothing like X11 except in broad concepts that all display / input APIs share - listening for input events, connecting to a display, creating a drawing area and so on. It's just that Wayland's map onto modern concepts such as GPU surfaces and compositing so that rendering is as efficient as possible.

As for the primitives, nobody has ever said they slow modern clients. The point is that clients don't even use the primitives any more and its the same story applies for most of the rest of X11. It has a 1980s 2D-centric, damage based view of the desktop and extensions are used to fool it into supporting surfaces and composition. But those extensions are workarounds which are design compromised by the architecture and so they are slower and less efficient than they would be.

Hence the push for Wayland. It will ultimately lead to a more lightweight and responsive desktop. Fedora Core 23 will be released soon and GNOME 3 should be feature complete for Wayland. And 24 might flip the switch and make Wayland the default. It doesn't stop people using X11 if they want so I don't see the problem.

Comment Re:I guess they realised... (Score 1) 138

X11 isn't perfect. Nobody's ever argued that. It's just nobody's really asking for a replacement, and if they were, they wouldn't be asking for Wayland. X11 is an extraordinary piece of technology, it takes some gal to claim everyone should just throw it out and replace it with a ground up rewrite that adds no new features and doesn't support the major features X11 is famous and loved for.

I think you'll find lots of people are asking for a replacement, starting with the people most familiar with X11. And more generally anybody who wants Linux to be able to host a modern, responsive desktop experience without suffering the latency and other bottlenecks of an arcane and mostly obsolete architecture for no reason whatsoever.

Comment Re: ZFS is nice... (Score 1) 269

But it's combined by the user at runtime, not by canocal. The GPL allows an end users to do this.

This is a way that people kid themselves about the GPL. If the user were really porting ZFS on their own, combining the work and never distributing it, that would work. But the user isn't combining it. The Ubuntu developer is creating instructions which explicitly load the driver into the kernel. These instructions are either a link script that references the kernel, or a pre-linked dynamic module. Creating those instructions and distributing them to the user is tantamount to performing the act on the user's system, under your control rather than the user's.

To show this with an analogy, suppose you placed a bomb in the user's system which would go off when they loaded the ZFS module. But Judge, you might say, I am innocent because the victim is actually the person who set off the bomb. All I did was distribute a harmless unexploded bomb.

So, it's clear that you can perform actions that have effects later in time and at a different place that are your action rather than the user's. That is what building a dynamic module or linking scripts does.

There is also the problem that the pieces, Linux and ZFS, are probably distributed together. There is specific language in the GPL to catch that.

A lot of people don't realize what they get charged with when they violate the GPL (or any license). They don't get charged with violating the license terms. They are charged with copyright infringement, and their defense is that they have a license. So, the defense has to prove that they were in conformance with every license term.

This is another situation where I would have a pretty easy time making the programmer look bad when they are deposed.

Comment Re:I guess they realised... (Score 1) 138

Exactly. X11 was designed for a different world where there was clipping, damage, rendering primitives, immediate rendering etc. It doesn't have any concept of compositing or GPU surfaces and thus a raft of extensions have appeared to support those things. But of course they're still hampered by a brain damaged pipeline which still thinks in the old way and they are constrained by.

Comment Re:ZFS is nice... (Score 1) 269

Uh, that doesn't work. The problem is that doing exactly what you've written down is contriving to avoid your copyright responsibility by deliberately creating a structure in someone else's work which you believe would be a copyright insulator. If you went ahead and did this (I'm not saying that you personally would be the one at Ubuntu to do so), I'd love to be there when you are deposed. Part of my business is to feed attorneys questions when they cross-examine you. I have in a similar situation made a programmer look really bad, and the parties settled as soon as they saw the deposition and my expert report. See also my comment regarding how Oracle v. Google has changed this issue. You can't count on an API to be a copyright insulator in any context any longer.

Comment Re:ZFS is nice... (Score 1) 269

I think you need to look at this in the context of the appeal of Oracle v. Google. We had a concept of an API being a boundary of copyright based on 17 CFR 102(b) and elucidated by Judge Walker's finding in CAI v. Altai. That stood for a long time. But Oracle v. Google essentially overturned it and we're still waiting to see what the lower court does in response.

Truly simple systems... require infinite testing. -- Norman Augustine