I've finally completed my new gentoo system install.
These are the main improvements over the first one:
linux-2.6.14-gentoo-r4 kernel with preemption enabled (smp too)
nptlonly glibc
modular xorg-7
/boot separated from / (root is reiserfs, boot is ext3)
My first impressions aren't bad: with exa acceleration method I can have the composite extension (mostly shadows) running smoothly!
BUT, I still have to understand why glxgears gives me at least 60fps less than the last time. Maybe I've got one clue: it seems the chipset being recognized is R200 instead of R350 (Radeon 9200). I also don't know if it's better to set driver to "ati" or "radeon".
In general, it seems the whole system is a little slowed down (xorg takes a lot to start, for example), but this occured upgrading from 2.6.10 to 2.6.13 already and nobody explained the behaviour.
I wonder if preemption or some other feature is behind this...
Another strange thing is that both "bmp" and "xfmedia" music players (both based on libxine) crash when I try to play mp3 files. Though, xmms plays them without problems
All in all I'm still very happy to have an updated system.
All in all I'm happy to have an up to date system and I look forward to have it doing everything like before.