Samuel A. Falvo II wrote:
On 7/26/05, Jakub Piotr Cłapa <[EMAIL PROTECTED]> wrote:
What? IP-domain? And what about SHM and Unix sockets? The network
transparency of X Windows is not the source of poor performance...
Actually, considering how verbose X11 protocol is "over the wire," yes
it is. However, you are correct that X11 itself isn't the problem
here. GTK is more than an order of magnitude slower than raw X11 (as
aptly demonstrated by comparing PCB and gPCB's performance on the same
hardware) is.
X11 is verbose but function calls aren't free either (especially when
there are context switches involved) so I don't think the usage of
sockets (UNIX or TCP/IP) is a real problem. The inefficient usage of
them although probably is. I have seen comments on the inefficiency of
modern toolkits and the amount of round-trips they require (when they
aren't really needed) rendering the whole X11-as-a-networking-protocol
almost unusable and killing the really cool thing the X11 architecture is.
Btw. The pure Xlibs solutions aren't ideal either. Killing the app
simply because the connection to the X server broke kind of sucks. (and
is really absurd because one of the key points in the wish list when the
protocol was designed was to actually allow you to move apps between
displays without an effort).
Also, the presence and utilization of SHM are negotiated via the
socket. I believe, IIRC (and I could be wrong), that ONLY data is
transferred via SHM. Actual X protocol commands are still sent via
the socket.
AFAIK you are right but that still makes quite a big difference (sending
images over the pipe almost certainly would result in big lags).
--
Regards,
Jakub Piotr Cłapa
