Short bio: Computer Scientist, FOSS supporter (read more)
Tux Machines (TM)-specific
With Thursday's announcement that Mir will ship by default in Ubuntu 13.10 on the desktop, many Ubuntu users were caught by surprise that this experimental display server will be ready by October. At Phoronix we have already carried out our first Mir benchmarks.
Unity in Ubuntu 13.10 is using XMir, the X11 compatibility layer for Mir, to run the current Unity 7 desktop environment atop Mir. XMir allows X11 applications to run on Mir in a similar fashion to XWayland and the X window application contents are then passed to Mir as just a single window. Without the desktop natively supporting Mir, there's an extra step in the rendering process with going through XMir, which is where curiosity arises about any performance penalties compared to just running an X.Org Server outright on the hardware.