LCA 2013 videos: X.org's shortcomings and Wayland

A slide from Stone's presentation. The organisers of the 2013 linux.conf.au (LCA) conference recently held in Canberra, Australia, have published videos of many of the conference's presentations. Among the videos, which can be viewed as either MP4 or OGV files, are several presentations dealing with support for graphics hardware in Linux. In a talk titled "The real story behind Wayland and X" (OGV, MP4, slides), long-time X.org developer Daniel Stone describes the X.org server's shortcomings and lays out how Wayland solves those problems, making it a better solution for the future. Stone apparently wanted to respond to all the criticism of Wayland and adulation for X.org that he sees so often in online forums.

In the presentation, Stone, who worked on the modularisation of X.org around the time of version 7.0, describes some internal workings in X as "basically, terrible" and absurdly complicated. To overcome the X server's problems, the X clients do a lot on their own, with the window manager practically turning into a second X server. These days, he says, X can no longer boast network transparency, despite many comments on forums, but just network capability, since many of the interfaces used don't work over the network. The techniques currently available on the X server make users look like amateurs compared to other platforms, in his experience.

Daniel Stone presenting at LCA 2013.
Stone goes on to explain that although the X server hardly does anything important any more, clients still have to communicate frequently with it, for no good reason, leading to a delay of at least half a second when opening Chrome, according to his measurements. He even recorded a delay of 1.4 seconds when opening Gedit under bad conditions; the editor and the X server used that time to unnecessarily communicate. After describing a number of such shortcomings, Stone explains how Wayland does things better; the network capabilities that are in development for Wayland, for example, are better than X's – they certainly "can't be worse than X".

Other important X developers are featured in some of the other presentation videos, like Mesa 3D developer Eric Anholt's "Linux Gaming at Last! Tuning Open Source Graphics Drivers for Valve Software" and "Teaching the X server new tricks" with David Airlie, who maintains the kernel subsystem with the KMS graphics drivers and contributes to X.org. The conference programme also included a number of presentations on other topics, such as RAID, OpenStack and Puppet. In some cases, the server with the videos cannot be reached with IPv6; IPv4 works better, but the response times are very high.

The organisers of FOSDEM 2013 are also currently working on putting videos of some conference presentations online. Videos of presentations on Samba 4 and the current state of Systemd development are already available.

(djwm)