Re: Snappy GUI response

Alan -

Since I know you have a more intimate knowledge of the many
interactions than most, I'm curious about the way you came to the
conclusions that you posted about.

On Thu, Jul 03, 2003 at 02:22:10PM -0400, Alan Cox wrote:
> From my own poking around the main reason people see lack of snappy
> performance is twofold
> 
> 	-	Using unaccelerated X setups
> 	-	The lack of render acceleration

I'm a bit confused. The way I read your comment, you're implying that
some people do see snappy performance with accelerated X setups.

I've informally experimented with end-user performance issues on a
large variety of machines over a long span of time and I've never seen
a configuration on which Linux and XFree have performance and
responsiveness at all compariable to Windows on the same hardware --
even with accelerated servers. Have you?  [ I wish I had rigorous
numbers to back that up but I don't. ]

On the flipside, some Linux applications have shown good
responsiveness outside of X11 even without acceleration. (svgalib doom
comes to mind)

Can you reply privately and tell me what machine I need to assemble to
get this snappy Linux/Xfree setup?

> Once apps are running the big one is the lack of support in X
> drivers for "dma block from screen to ram" or "dma block from screen
> to agp space" both of which would make unaccelerated render way way
> faster

I don't see how this is relevant. IMO, the responsiveness problems of
X11 predate AGP. Can you point to a PCI platform where display
performance is comperable on X11 and Windows?

On Thu, Jul 03, 2003 at 04:49:29PM -0400, Alan Cox wrote:
> David Jeske wrote:
> > IMO, a bigger contributing factor is that the X design does not have
> > application performance as its number one objective, and the resulting
> 
> Wrong. When X was designed every clock counted. 8Mhz was "elite cool
> workstation to fight over"

I don't understand your comment here. Are you being sarcastic? or are
you saying that you think when X was designed performance was the
number one objective?

My understanding is that X10/X11 was designed specifically to solve a
problem at MIT. They needed a platform-independent graphics system
because they couldn't standardize on a single platform. I'm sure they
tried to make it fast, but I can't find any reference which says that
was the primary goal of the system.

  http://www.wikipedia.org/wiki/X11
  http://www.rahul.net/kenton/gettys10.html
  http://www.dubois.ws/software/imake-stuff/fulton.pdf

<humor>
Besides, we all know that the first priority of all computer systems
is to display porn:

  http://www.mit.edu/activities/safe/cases/e-images/mit-xpix-dir-history
</humor>

-- 
David Jeske (N9LCA) + http://www.chat.net/~jeske/ + [email protected]