Bug#697727: xserver-xorg-video-radeon: [radeon] Scrolling in xterm slow with KMS

[Tilo Schwarz]

On Thu, 10 Jan 2013 10:34:07 +0100, Michel Dänzer <daenzer at debian.org>  
wrote:

> On Don, 2013-01-10 at 10:14 +0100, Tilo Schwarz wrote:
>> On Thu, 10 Jan 2013 09:16:37 +0100, Michel Dänzer <daenzer at debian.org>
>> wrote:
>>
>> > On Mit, 2013-01-09 at 20:01 +0100, Tilo Schwarz wrote:
>> >>
>> >> Indeed, using
>> >>
>> >> % grep ColorTiling /etc/X11/xorg.conf
>> >>          Option          "ColorTiling"   "off"
>> >>
>> >> the scrolling is twice as fast as without this option (from 12sec  
>> down
>> >> to
>> >> 6sec). That is still almost three times slower than without KMS, but
>> >> already much more usable!
>> >
>> > The better solution would be to configure your terminals to use
>> > fontconfig/Xft for text rendering.
>>
>> Do you have a link to "the correct debian way" to enable fontconfig/Xft
>> for text rendering? (Me being no X11 expert ...)
>
> It's app/toolkit specific. E.g. with xterm you can enable it with -fa
> and related options.
>
>
>> Is it a fontcontig and Xft, or is it a either fontcontig or Xft?
>
> It's mainly about Xft. Most users of that also use fontconfig for
> selecting the fonts to use, but that's not required.
>
> Most apps/toolkits have used the modern text rendering infrastructure by
> default for a long time, but a lot of terminal emulators are still
> holding out for some reason.

One last addition. I worte "... rxvt-unicode, which has xft support."

But accoding to the rxvt-unicode man-page, my xresource "urxvt*font: 9x15"  
does not select a xft font, because urxvt uses x fonts by default. So  
urxvt is able to scoll fast although no xft font is used. Running "ltrace  
urxvt" shows, that xft funcions are only called, if I specify the font  
with "xft:9x15".

Regards,
	Tilo