Rendering RGBA images is awfully slow with Konqueror web browser (and with other Qt applications) with XAA since upgrade from 6.8 and haven't improved since then. I use Linux and DragonFly BSD with ati, mga and nv drivers and all these have the problem. Good testcase is viewing screenshots in http://kde-apps.org/content/show.php?content=10187 . With first two screenshots Konqueror really lags - it's slow to open, scroll and move window. But there isn't any slowdown with third screenshot. First two screenshots are 8-bit/color RGBA images, third one is 8-bit/color RGB image. Although Firefox handles these images significantly better, there is noticeable slowdown in it as well on slower machines. There is no problem with EXA (tested with ati and xorg 7.1), but EXA is currently broken in xorg 7.2 and isn't available at all for nv. I'm almost sure that it's a regression - the problem appeared with xorg 6.9 - I still have some machines with XFree86 and there is no problem with them.
This is old. XAA is old and crufty and won't be seeing performance improvements. If you can provide a patch to fix this, however, it will be considered.
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