Blauzahl asks where to file
bugs we encounter in the nvidia drivers. Last night, after my
previous blogentry
Fredrik told me he disagreed that it’s hard to find nvidia engineers
that can help with this kind of performance problems. It seems some hang out in
#xorg-devel, and our planet admin Chris Lee is currently working on the NVidia
Linux team as well. Fredrik pointed me to a benchmark that measures the performance
of various XRender calls. Running it shows that most of the tests are
very fast (1 – 20 milliseconds) or very slow (most between 8 and 16 seconds).
That means lots of operations take 400 times as long as others. On my notebook’s
ati x1300 using the fglrx driver, I get results of 20 milliseconds for the ‘faster’
operations. Not a single test takes more than 2.5 seconds. So nvidia is faster
, but only for some tests. Overall, ATI performs better in these tests. And then
maybe those operations can be accelerated in the driver. xrenderbenchmark
takes ~13 minutes on my nvidia 7600GS
and 1:45 on my ati x1300, a fairly low-end laptop chip. In order to compile
xrenderbenchmark, first “qmake xrenderbenchmark.pro” (make sure you use Qt4’s
qmake). Then run make, and xrenderbenchmark.
get Zack’s
benchmark and provide the data to the nvidia developers. The problems should
be filed as a bug on the product xorg, component “Driver/nVidia (proprietary)” on bugs.freedesktop.org. I’ve
filed the performance issues here,
along with some my logfiles. Update: I’m not the first finding out about this.
Nice pictures showing the performance
problems and lots of reports on the
Phoronix forums. All
reporting abominable 2d performance with NVidia graphics cards and drivers.