Lead Mir Developer: 'Mir More Relevant Than Wayland In Two Years'

M-Saunders writes Canonical courted plenty of controversy with it announced Mir, its home-grown display server. But why did the company choose to go it alone, and not collaborate with the Wayland project? Linux Voice has an interview with Thomas Voss, Mir's lead developer. Voss explains how Mir came into being, what it offers, and why he believes it will outlast Wayland.

Comments

Re:I still don't see what's wrong with X

[jbolden]

Seriously, what's so broken about X?

There are 3 situations involving applications, networking and graphics
a) Running an application on a machine sharing ram with the video card.
b) Running applications on a machine close enough to the video card that the latency between them is lowish and the bandwidth is plentiful and performance is irrelevant.
c) Running applications on a machine where either the latency is high or the bandwidth is limited
X11 does terrific for (b) in exchange for damaging (a) and (c). X11 was designed in a world where (b) is common. In today's world (b) is uncommon.

Other issues:

1. The mixing of signed and unsigned coordinates causes problems both in the protocol, where 3/4 of the coordinate space is often unrepresentable, and in the C language bindings.
2. The X protocol is asynchronous for efficiency: in general, neither the server nor clients wait for replies. But the protocol’s synchronization mechanisms are insufficient, and leave many unavoidable race conditions.
3. The X protocol attempts to be policy-free and tries not to dictate any particular style of window management. However, some desirable window manager features cannot be implemented correctly, because there are window attributes which the window manager can neither fetch nor monitor.
4. The X protocol provides visibility notification events so that clients can avoid computation of obscured window contents. However, this notification doesn’t work well for nested windows or for windows with backing store.
5. None of the several ways that an application can implement interactive mouse tracking of crosshairs, bounding boxes, etc., allow both efficiency and correctness.
6. Popping up menus and dialog boxes is slow because it requires too many round trips and generates too many events. Repainting when portions of a window become visible is often slow.
7. Exceptional conditions are poorly handled. Faulty programs can freeze the server, and clients cannot kill queued requests if the user doesn’t want to wait for the server to finish servicing them.