Antialised fonts and drawing speed issue (emacs 23.0.60)

Antialised fonts and drawing speed issue (emacs 23.0.60)

[E.L.K.]

Hello!

I'm using emacs 23.0.60 on Linux with font "DejaVu Sans Mono".

And I'm expiriencing slowness when redrawing buffer filled with
any text (doesn't matter - with any font-lock or without).

For example, if i fill all buffer with "0" then repainting of all
emacs window, when scrolling (with C-v, M-v), takes about 1 sec
(or a bit less, but i can really see how it redraws window
line-by-line).

I googled about this problem, and find nothing, except one email
conversation in this mailing list:
http://lists.gnu.org/archive/html/emacs-devel/2008-04/msg00045.html
which seems describing very similar problem.

I've tried to checkout and build last version from CVS and it
seems to have same issue. 

I've tried on another machine to run 23.0.60 version, and there
is same problem. 

On Windows, no such problem was seen by me.

Machines configuration: 

1. Compaq Evo n800c notebook"
2.2 GHz Pentium 4-m
1024 mb RAM
video: ATI mobility Radeon 7500 (32 mb)
videodriver: "radeon"

2. Desktop
2 GHz Athlon-XP
512 mb RAM
video: GeForce MX400 (32 mb)
videodriver: "nv"

Additionally, i've tested on 1st and 2nd machines xterm redrawing
with same font and don't see this trouble on xterm (so, painting
can be fast), on 2nd machine it was noticeably slower, but not as
slow as drawing in emacs. 

What else information can I provide or tests can i do, to collect
more information to help trace this issue? I have rater big
amount of free time now and will be happy to help make emacs
better. (:

Sorry for my english.

-- 
E.L.K.
Saturday, 07 of June, 2008, 13:34

зы. C_U_L8r!

Re: Antialised fonts and drawing speed issue (emacs 23.0.60)

[Óscar Fuentes]

"E.L.K." <some.any.key@gmail.com> writes:

> Hello!
>
> I'm using emacs 23.0.60 on Linux with font "DejaVu Sans Mono".
>
> And I'm expiriencing slowness when redrawing buffer filled with
> any text (doesn't matter - with any font-lock or without).
[snip]
> On Windows, no such problem was seen by me.

On Windows, Emacs with the new font backend is so slow that is unusable
on low-end machines (read old machines or laptops on power-saving mode).

[snip]

> What else information can I provide or tests can i do, to collect
> more information to help trace this issue? I have rater big
> amount of free time now and will be happy to help make emacs
> better. (:

Profile and optimize the C code? That's what I plan to do at some point
on the future.

-- 
Oscar