Mir is to ship as the default display server in Ubuntu 13.10, Ubuntu have today announced.

Canonical’s XServer replacement will be used to help power the Unity 7 desktop on devices with open-source graphics card drivers.

Unity 7 will run atop of XMir, an implementation of X that provides a compatibility layer that allows software, desktop environments, peripherals and multi-monitor setups designed for X to continue to work as expected.

But while Mir and XMir will be shipping in October’s release by default, not everyone will be able to use it.

Those with proprietary graphics card drivers installed (NVidia, ATi, etc) will instead be served with the traditional XServer windowing system as a fallback.

This fallback is necessary because, at present, GPU vendors don’t provide support for Mir/XMir in their binary drivers – a situation expected to be resolved by the release of Ubuntu 14.04 LTS next year.

Xmir is already able to run most desktop environments competently, including LXDE and KDE, as the following video shows:

‘Why Now?’

So why now? Why as default in Ubuntu 13.10?

‘Putting Mir front and centre on the Ubuntu desktop so soon is a risky move – but it’s also an unavoidable one…’

To meet the goal of shipping Mir as the only default in Ubuntu 14.04 LTS, and powering whatever Ubuntu handsets OEMs are looking to ship in the meantime, Mir (and XMir) need to be production ready as soon as possible.

So while putting Mir front and centre on the Ubuntu desktop so soon is a risky move it’s also an unavoidable one if it’s to succeed. Real-world usage will give developers stronger feedback to help in shaping, optimising and honing the feature.

As Canonical’s Olli Ries explained to me earlier today:

“Mir has reached a level of maturity in terms of quality and performance which allows us to make it a core component for Ubuntu 13.10. With its current design, we enable all dependent derivatives to run unmodified on top of this new stack.

Integrating Mir today gives Ubuntu one additional cycle to enhance performance and further integrate it in in order to have another first class Ubuntu LTS by 14.04.”

Mir was created to aid in Canonical’s convergent goal for Ubuntu – to have the same code running across smartphones, tablets and TVs. As form-factors scale so too must the display technology driving them; a lighter and more flexible solution was needed that that provided by existing projects.

XMir, which runs on top of Mir, and will front the Unity 7 desktop in 13.10, is used to provide backwards compatibility for applications and services that rely on X.

What This Means To You

Enthusiasm about the technology in this change aside, this change will actually mean little by way of visible changes.

Whether you end up using a Mir-powered desktop, or one using XServer, the actual desktop experience in Ubuntu 13.10 should be the same.

And, for most of us, that’s all that matters.

If you’re running Ubuntu 13.10 already and would like to get a head-start on trying Mir you’ll find all you need to know in this blog post.