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ubuntu Mir: Ubuntu's New Display Server

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I'm pretty sure the drivers are already run in the kernel, but most of the actual managing is done by X11 in userspace (Which causes issues as the app and kernel fight for the same device). The main benefit of stuff like KMS and GEM is that it moves resource allocation and control out of X and into the kernel (So instead of a userspace application directly allocating memory on the GPU, it asks the kernel to, making it responsible for the memory)

Putting stuff in kernel space does increase the chances of an error taking down the system, but you already have that issue with existing device drivers (If your SATA controller driver has an error your system will crash and possibly corrupt your HD, etc.), and ideally the kernel should be resilient to certain hardware issues (I'm pretty sure the Intel drivers are capable of resetting the graphics hardware in case of an error/crash). Of course in a perfect world we'd be running a microkernel and doing everything in userspace, but it's not a perfect world.

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Of course in a perfect world we'd be running a microkernel and doing everything in userspace, but it's not a perfect world.
A formally verified microkernel would cure cancer.

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Of course in a perfect world we'd be running a microkernel and doing everything in userspace, but it's not a perfect world.

My understanding is that we generally don't use microkernels because of context switching. Some part of the kernel has to operate in kernel mode, and although it is theoretically more secure to run as much as possible in userspace, the latency introduced by context switching makes it practically infeasible.

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Isn't that what minwin in 7 and 8 does

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Isn't that what minwin in 7 and 8 does

A microkernel? Microsoft has toyed with the idea in the past, but I don't think any shipping version of Windows has featured a microkernel. The Windows NT kernel architecture is inherently monolithic. Wikipedia seems to support this assertion.

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As long as I can keep running Openbox via LXDE, I don't care what they use.

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A microkernel? Microsoft has toyed with the idea in the past, but I don't think any shipping version of Windows has featured a microkernel. The Windows NT kernel architecture is inherently monolithic. Wikipedia seems to support this assertion.

read the kernel part of that wiki document again. while the kernel has advanced from the original microkernel, the actual kernel, layered between executive and HAL is referred to as a microkernel.

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read the kernel part of that wiki document again. while the kernel has advanced from the original microkernel, the actual kernel, layered between executive and HAL is referred to as a microkernel.

From what I understand, everything that runs in kernel mode is part of the kernel. What constitutes a microkernel is services running in user mode that are essential to kernel operation (i.e. services that would otherwise run in kernel mode). Since Linux internally separates the HAL, VMM, and other essential kernel components, does that make it a microkernel too? I admit, this argument depends entirely on your definition of what exactly constitutes the "kernel". The definition seems somewhat malleable considering modern abstracted software design. The introduction of the "Architecture of Windows NT" Wikipedia article seems to compromise on this point too by claiming, "The Windows NT kernel is known as a hybrid kernel."

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From what I understand, everything that runs in kernel mode is part of the kernel. What constitutes a microkernel is services running in user mode that are essential to kernel operation (i.e. services that would otherwise run in kernel mode). Since Linux internally separates the HAL, VMM, and other essential kernel components, does that make it a microkernel too? I admit, this argument depends entirely on your definition of what exactly constitutes the "kernel". The definition seems somewhat malleable considering modern abstracted software design. The introduction of the "Architecture of Windows NT" Wikipedia article seems to compromise on this point too by claiming, "The Windows NT kernel is known as a hybrid kernel."

Yea I would say NT is more a hybrid kernel. Also not everything that runs in kernel mode is the kernel. Windows has the ability to run third party code in kernel mode. Linux is a better example of an actual monolithic kernel.

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The X.Org Foundation Is Undecided About Mir

The X.Org Foundation hasn't firmly decided on their position of Canonical's Mir Display Server versus Wayland.

The meeting logs for an X.Org Foundation Board of Directors' IRC meeting from earlier this month have finally been published to the X.Org Wiki.

Oracle's Stuart Krietman began by asking "does anyone here take seriously the 'threat' of Mir?" Bart Massey responded, "Wayland is something we have agreed is part of the X.Org umbrella; Mir definitely is not." But he then said, "I would suggest we make a highly supportive and encouraging announcement [regarding] Mir...Emphasize that we think that it would be fantastic if Canonical could replace X on desktop in 12 months... All I meant is that we haven't yet taken a position on Mir."

Bart also added, "Given that Mir is a single-corporation effort, I don't think it's appropriate for us to be supporting it, but that's just my position..." Intel's Eric Anholt wrote, "I don't imagine many people seeing mir as the next big thing." AMD's Alex Deucher commented, "I mean if mir took off, we could support it as well."

This meeting took place two weeks ago and there was an action item for the foundation to issue a public statement about Mir, but so far that's been non-existent.

Source: http://www.phoronix.com/scan.php?page=news_item&px=MTMzMDM

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Wait what, X.org foundation consists of members from intel and AMD? I never knew them, nifty! :p

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I don't think I've seen any issue that enraged the Linux community like this in a long time.

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I don't think I've seen any issue that enraged the Linux community like this in a long time.

Yea...this whole thing makes very little sense to me.

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Yea...this whole thing makes very little sense to me.

It's a strange form of vendor lock in, apps that depend on the Mir API won't be able to run on other Linux distros (Compare that to Wayland which can be implemented by anyone on any OS)

People are upset mainly because Canonical is doing their own thing with no input from anybody else while also saying the competing projects are bad.

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It's a strange form of vendor lock in, apps that depend on the Mir API won't be able to run on other Linux distros (Compare that to Wayland which can be implemented by anyone on any OS)

People are upset mainly because Canonical is doing their own thing with no input from anybody else while also saying the competing projects are bad.

(Sorry in advance if this has be said before).

How is it vendor lock in? If Wayland can be implement on any linux distro, what prevents Mir from also being implemented on any Linux distro. The only requirement (as far as I'm aware) for either one is someone who cares enough. Without that...wayland would have the same issue.

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No other distro wants to use Mir, nobody other than Canonical is pushing it (Nevermind the KDE/Gnome devs are all behind Wayland, so any distro that wants Mir would need to rely on Canonical's forked versions of those libraries) And the only Mir display server is going to be Unity, so the distro will either have to write their own or use Canonical's code.

And people have an issue with the Canonical CLA, which gives them the right to take the code and re-license it under a proprietary license at any point (Compare this to something like the KDE agreement, which explicitly forbids that)

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It's a strange form of vendor lock in, apps that depend on the Mir API won't be able to run on other Linux distros

Other than Unity itself, apps shouldn't care about what display server they are running on.

At worst you won't see Unity running anywhere besides Ubuntu... which you aren't seeing right now anyway for a different set of reasons.

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