Not to thread the X server

[Juliusz Chroboczek]

Lukas,

Please relax.  This is a technical discussion, and we're disagreeing
on technical, not ideological grounds.  There's no point in getting
heated up until Tiago has published some tentative conclusions for his
(very interesting) investigation.

> Well, while the world is moving towards hundreds cores CPU, you
> would like to stuck with old school single core Xserver

While the world is moving towards complex NUMA architectures, you
would like to stick with an old-school single-image multithreaded
process?

> I think that Xserver should be highly multithreaded, mainly CPU consuming
> parts should be done in parallel.

I think that the my desktop should consist of a number of compute-bound
processes running in parallel, with the X server being a lightweight
process that doesn't execute any CPU-intensive code.

The client-server architecture of the X protocol should be able to
support such a style of programming (although the Xlib implementations
do not necessarily), but we need to get rid of some post-X11R4
extensions that cause compute-bound tasks to be performed by the
server (notably core fonts and GLX) and of some brain-damaged
X clients that think that the server's pixmap space is a good place to
stash your music collection.

> Also the driver of video card should be reentrant and able to run in
> threads. If you realize that a graphic hw consists of multiple
> rendering units, the drawing software should also consists of
> threads.

Please correct me if I am wrong, but I was under the impression that
there is only one command pipeline on a GPU, no matter how parallel.

                                        Juliusz