Hi,

I've gone from Debian Lenny to Squeeze recently and managed, with the kind help of LQ by disabling modesetting, to get it booting into X with my Radeon HD4650 AGP (using FGLRX). Mostly it is going well but I could do with some info on the state of compositing, I'm in no real rush to use it but seeing as it is included with KDE4 & I think it was even enabled automatically on my system, I'd like to see if I can get it to work properly.

Compositing as such works, however the poor performance when resizing a window causes me to simply disable it. FPS drop from 100 to single figures when resizing windows. I can move windows without such a big performance hit. I've played around with the various setting in the advanced settings etc., but nothing in there resolves it. I've tried different Catalyst drivers too but still no improvement.

If you want to see a video of this problem please Google 'kwin resizing' and watch the first video from 02/Aug/2009.

I've been Googling for the last few nights about this & it seems to be a well-known issue(*) not just for ATI but also NVIDIA hardware but to a lesser extent, but I've not yet found a solution myself. The hardware vendors blame Kwin & Xorg, and vice-versa. There is some partial-solution where you can edit code & recompile the Xserver(**), but it supposedly can cause screen artifacts & I really don't want to go recompiling Xserver.

Does anyone know the status of this issue, has it been fixed, is there an easy workaround, or is it currently still an unresolved issue?

Thanks,

Philip.

PS: sorry if this is the wrong forum section, I'm not sure which it should go in.

(*): http://blog.zx2c4.com/169
(**): http://blog.zx2c4.com/190

What version of fglrx are you using?

Adam

Thanks for the reply.

CCC reports Catalyst Version 10.11, but I've tried the last two 9.x versions & all of the 10.x series and none of them fix the problem. I think I'm really running 10.4, as it seemed to be the smoothest for non-compositing desktop. I didn't manage to find out how to fully remove all FGLRX files manaully as I was investigating this at one point. I think CCC reports 10.11 as I suspect I've installed various FGLRX dirvers without always having run /usr/share/ati/fglrx-uninstall.sh first, but I would have thought it does this automatically upon installation...

The 9.x series just doesn't work with 2.6.32 kernels, as is in Squeeze.

Unfortunately, resizing windows under compositing with fglrx has been slow for quite a while now. The last few versions of fglrx have new acceleration code which might improve things, but I've never really tested it myself. I thought the code was enabled by default, but you might want to try 10.11 or 10.12 and see if fglrx is still using the older, slower, XAA acceleration.

Adam

I've just re-tried both 10.12 & 10.4. Neither fixed the problem. I find 10.4 slightly better for 2D without compositing anyway so I'm sticking with it for now.