Robert Ancell, a Canonical software engineer, wrote a blog titled ‘Why the display server doesn’t matter‘. He argued that “Display servers are the component in the display stack that seems to hog a lot of the limelight. I think this is a bit of a mistake, as it’s actually probably the least important component, at least to a user.”
Mark Shuttleworth, the founder of Ubuntu and Canonical said, “Robert explains why the display server is a piece that matters most in its quality for the platform provider, and least to application developers. It was amazing to me that competitors would take potshots at the fantastic free software work of the Mir team, knowing it really doesn’t affect users at all.”
There has been a lot of discussion going on around the future display server for Linux. It was meant to be Wayland which was being developed as the successor of X, developed by the same experience team. However, despite initial commitment Canonical secretly worked on their own server for over 9 months and then announced it as MIR, which created quite a stir in the community as most community members felt betrayed. There was a heated discussion as Canonical developers posted a lot of wrong information about Wayland when announcing Mir, which further distanced them from the larger open source community which was putting its weight behind Wayland.
The blog post by Robert triggered another set of discussions as KDE developers, who do have long experience with Qt (something Canonical is moving towards for it’s mobile ambitions), have refuted Bob’s claims and said that display server does matter.
Martin Gräßlin, a leading KDE developer who maintains KWin, picks this quote from Robert:
The result of this is the display server doesn’t matter much to applications because we have pretty good toolkits that already hide all this information from us.
Martin says, “Now I don’t know how to put it, the best description is that I’m shocked that Canonical is still not seeing the problems they created by having multiple display servers. I do not know how much experience Robert has with making applications work with multiple display servers, but I at least have this experience as shown in my blog post on making KF5 not crash on Wayland. Granted in this blog post I write that “basically if your application compiles on frameworks it will run on Wayland out of the box”. But that is a strong simplification of the issues which can be present.
Martin wrote a long blog to show why he thinks Robert is wrong about Display server which you can read here.
Another lead KDE developer who leads the development of Plasma Desktop, Aaron Seigo, also refuted Robert’s claims and pointed out how it matters to almost every stock holder — from a user to a developer.
Aaron also raised the problem which the larger Free Software community is trying to fix – reduce duplication of work. He says, “We have been working to resolve unnecessary duplication in the Linux stack for years, and we have had great success in that direction. Sometimes it meant sacrificing things we had developed (anyone still remember aRts? but usually it just meant finding common ground and making sensible decisions together from there. The Linux desktop is more consistent and coherent today than it ever has been as a result, from icon themes to clipboards to compatibility between window managers to IPC to application notifications to application launching to multimedia to … we’ve been fixing divergence one piece at a time for over a decade, and every time we’ve done that we have benefited as users and freed up developer resources.”
Canonical showed wisdom recently by dropping its own Upstart and chose systemd which it initially criticized as NIH, invasive and ‘hardly justified’. The Free Software community is expecting that Canonical will show prudence and drop their MIR and adopt Wayland. Canonical has great ambitions with Ubuntu, their struggle is much bigger so it may be wise for them to use limited engineering talent to tackle the issues Ubuntu is facing in desktop and mobile space by using the technologies being develop by the larger Free Software community.