Re: [xougen] General X qestion

[Alan Cox]

On Llu, 2003-09-15 at 19:16, Core wrote:
> Whenever I run an X program which displays bitmaps on a remote display,
> the act of moving a window over it makes it not only redraw, but pull
> all the graphics from the remote end all over again.

Not unless the program was written badly. X provides the notion of
images you can manipulate either server or client side. So good software
pushes the images it needs to the server once. A redraw then triggers
nothing more than a new draw request citing the image already held
remotely. Games like xmris do this to great effect and are playable over
the network as a result.

Backing store also helps in a lot of situations involving high latencies
or systems with a lot of RAM/video RAM. There are some tradeoffs because
of poor memory management between DRI and the X server (trivial patch to
hide the worst of it) but if you arent using DRI 3D options then its
often worth running X with

        startx -- +bs -wm

Which will make the server provide backing store for all mapped windows
cutting down on the traffic for expose events and redraws which can be
heavy and high latency on a network especially. Personally I find for
most setups those two options are better and feel snappier than the
default anyway, OTOH they'll *kill* a tiny machine..