4 ms·

This has probably been asked dozens of times, but honest question: how much of a technological dead end is the X11 architecture? Perhaps this ship has sailed,

by tcbawo 3y ago

This has probably been asked dozens of times, but honest question: how much of a technological dead end is the X11 architecture? Perhaps this ship has sailed, but what were the impediments to modernization? Lack of developer interest? Lack of consensus between stakeholders to make significant changes? I worry that other critical open source software projects will go through a similar lifecycle as it matures and the original developers retire. Considering the lineage of virtual consoles going back to physical teletype machines, it makes sense to preserve some form of feature compatibility with current software.

kevincox 3y ago
The problem is that the X11 architecture has been dead for a decade. The X11 architecture was network-transparent drawing primitives. Almost all of modern X is done via extensions. Your drawing is done using OpenGL or some similar interface, buffers are passed using shared memory, lots of display metadata and configuration is done via extensions as well. The actual rendering is done by the window manager (assuming you are doing compositing). As Daniel Stone said, all that is left of "Core X11" is really bad IPC. (As the client talks to X which talks to the window manager which talks to X which talks to the client, requiring 2 round-trips for every request) https://youtu.be/RIctzAQOe44?t=1037 https://youtu.be/RIctzAQOe44?t=1037 So saving Core X11 is a dead end. All you have is a basic IPC system with unnecessary round-trips. So all that is left to save is the extensions. You can save GLX and the Vulkan equivalent but tearing them from the IPC is leaving not much behind. So really, no. The things that could be saved are so basic (like feeding input events) that it is better to just re-implement them using a better IPC protocol. For clients that need backwards compatibility there is XWayland (although it is limited for security reasons).
- bzzzt 3y ago
  Everyone defending the X11 protocol nowadays should be forced to write at least one GUI app using just Xlib and Xt. I don't believe people are invested in the X protocol per se, but more the Xorg implementation that still offers a few interesting features not ported to Wayland yet. But allowing people to choose will mean any urgency of porting those features will diminish and you don't get feedback on Wayland from all those people who switch to X11. Linux users seem to be overrepresented at both ends of the conservative/progressive spectrum.

by tcbawo 3y ago

kevincox 3y ago

The problem is that the X11 architecture has been dead for a decade. The X11 architecture was network-transparent drawing primitives. Almost all of modern X is done via extensions. Your drawing is done using OpenGL or some similar interface, buffers are passed using shared memory, lots of display metadata and configuration is done via extensions as well. The actual rendering is done by the window manager (assuming you are doing compositing). As Daniel Stone said, all that is left of "Core X11" is really bad IPC. (As the client talks to X which talks to the window manager which talks to X which talks to the client, requiring 2 round-trips for every request) https://youtu.be/RIctzAQOe44?t=1037 https://youtu.be/RIctzAQOe44?t=1037 So saving Core X11 is a dead end. All you have is a basic IPC system with unnecessary round-trips. So all that is left to save is the extensions. You can save GLX and the Vulkan equivalent but tearing them from the IPC is leaving not much behind. So really, no. The things that could be saved are so basic (like feeding input events) that it is better to just re-implement them using a better IPC protocol. For clients that need backwards compatibility there is XWayland (although it is limited for security reasons).

bzzzt 3y ago
Everyone defending the X11 protocol nowadays should be forced to write at least one GUI app using just Xlib and Xt. I don't believe people are invested in the X protocol per se, but more the Xorg implementation that still offers a few interesting features not ported to Wayland yet. But allowing people to choose will mean any urgency of porting those features will diminish and you don't get feedback on Wayland from all those people who switch to X11. Linux users seem to be overrepresented at both ends of the conservative/progressive spectrum.