Antialiased fonts makes scrolling noticably slower

Antialiased fonts makes scrolling noticably slower

[paul r]

Hello,

I'm starting emacs 23.0.60, on gnu/linux
 - under X
 - with free ati graphic drivers (r350 IIRC)
 - 1.7Ghz x86 cpu
 - with option -fn "Dejavu Sans Mono-14"

In a long buffer, if I do
   C-u 1 C-v
, then I do
  C-x z  (holding this z)
to scroll line after line.

Buffer scrolling is slow, letter drawing make them blink, and cpu
peaks at maximum.
Do everybody experience slowness with antialiased fonts ? Is that
inherant to the hard work required to compute antialising, or to a
poor performance in 2D on my box, or something else maybe ?
Of course I do not experience this behaviour at all when antialiasing
desactivated.

Thanks

Paul

Re: Antialiased fonts makes scrolling noticably slower

[Gilaras Drakeson]

> I'm starting emacs 23.0.60, on gnu/linux
>  - under X
>  - with free ati graphic drivers (r350 IIRC)
>  - 1.7Ghz x86 cpu
>  - with option -fn "Dejavu Sans Mono-14"

Could you please try the radeonhd driver and confirm the issue there as
well?  On my machine, radionhd driver has been better and faster for
certain tasks.

--
Gilaras Drakeson

Re: Antialiased fonts makes scrolling noticably slower

[Stefan Monnier]

>> I'm starting emacs 23.0.60, on gnu/linux
>> - under X
>> - with free ati graphic drivers (r350 IIRC)

You mean the Xorg `radeon' driver?

>> - 1.7Ghz x86 cpu
>> - with option -fn "Dejavu Sans Mono-14"

> Could you please try the radeonhd driver and confirm the issue there as
> well?  On my machine, radeonhd driver has been better and faster for
> certain tasks.

Faster???? Really?


        Stefan

Re: Antialiased fonts makes scrolling noticably slower

[paul r]

2008/4/2, Gilaras Drakeson <gilaras@gmail.com>:

>
> Could you please try the radeonhd driver and confirm the issue there as
>  well?  On my machine, radionhd driver has been better and faster for
>  certain tasks.
>

Thank you for the tip. I do not think I will build manualy radeonHD
for my box, because of a lack of time. I can say that gedit does not
seem require as much computing. According to my CPU monitor, I would
say it requires 5 times less CPU as scrolls smoothly. So could it be a
driver issue ?