Buzzing (was :The forbidden topic: Glamo OpenGL)

Kishore kitts.mailinglists at
Sat Nov 15 16:37:25 CET 2008

On Saturday 15 Nov 2008 3:19:10 pm Carsten Haitzler wrote:
> On Sat, 15 Nov 2008 07:22:29 +0000 Stroller
> <stroller at>
> babbled:
> > On 15 Nov 2008, at 07:08, Kishore wrote:
> > > On Friday 14 Nov 2008 8:13:20 pm Gothnet wrote:
> > >> Also, I know everyone loves X, but is it really the best choice for
> > >> a low
> > >> powered device that needs a responsive UI?
> > >
> > > ...
> > > I still would like to know more in terms of performance and memory
> > > consumption
> > > and scalability.
> >
> > You guys should search some of Raster's previous posts on this
> > subject. Although you may have to go through quite a lot of posts to
> > find his comments (!), I think you will find he has stated more than
> > once that the performance of X is much maligned (as long as
> > programmers are sensible and use appropriate practices).
> indeed it is. i have seen x (+efl) drastically (by many times) outperform
> directfb - on the same device. every time someone thinks that the ui sucks
> and the solution is "dump x" it is almost always from a position of lack of
> knowledge just what is the cause of the problem. a bit of analysis and
> you'll find the problem is almost always one (or more) of
> 1. just bad hardware (affects everyone x and others)
> 2. incomplete or just bad drivers (not x itself and the same problem will
> happen anywhere you try and accelerate so if its within x or somewhere else
> - same problem).
> 3. simple bad x apps or toolkits doing things badly, inefficiently or just
> trying to do things in a way that just reacts badly with the target
> hardware.
> whatever you do in replacing x - you will just replace it with the same
> thing under a different name. you won't improve or solve anything, as long
> as you want to have more than 1 process be able to display. if it's only
> one, dumb-fb is an option but you still need to then do the whole toolkit
> so see the above problem list. and you just lost multi-process access, lost
> a lot of support for a lot of toolkits, apps etc. if you want to x CAN be
> used as a dumb-fb with little extra overhead.
> if you really want to sink a lot of time i can go into gory detail one
> thing at a time... but you can also just search these lists and save me the
> effort :) x gives you the ability to share input devices (kbd, ts, etc.)
> and share the screen. you want that. it is not big and fat. it is rather
> small and lean. extensions exist to do just about everything. very little
> does not exist in some x extension these days.

Raster! Wow! Thanks for the detailed response. Really good to know :)
Well, I certainly do not think that direct fb is a better option over X. It 
sure is crippling to not have multiple apps have access to the screen while 
not having to know about the others existence. What i was considering was X 
itself and its overhead. Its good to know that X does not add much overhead. I 
first got thinking about this when reading about gallium3d. I do recollect 
reading that the developers were developing it with hope to replace *most* of 
X and use X only as an interface/API. The reason for this they said was that X 
was bad.

Now, I do not personally know much about this. But it is of academic interest 
to me.

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