On Tue, 23 Sep 2003, Glenn Ramsey wrote:
I have a scientific visualisation app (cgui from
) that I have tested on 3 different
machines and I have found that the graphics performance is opposite to
what I expected. I was wondering if anyone could give me some pointers
about how to figure out what might be causing the slowness on 2 of the
The machines are:
1. Compaq Presario 2100 series laptop. Athlon XP 2400, 512Mb Ram, Ati
Radeon IGP320M. The accelerated features of this graphics chipset are
not supported by XFree86.
And you'll probably find the AGP bridge isn't either, which may be another
cause of slowdown. Oh, and the XFree86 DRI stuff won't help at all either
- the mainline X tree is *old* in this regard. If you're feeling brave,
check out the current XFree86 snapshots - ATI have been contributing a
*lot* of code, and I think they've got 2D acceleration for the ATI IGP
chipsets in there now (SWMBO has a laptop with one of these, and she's
asking me to do this...). If you're *really* lucky, the latest X snapshot
will actually build!
2. PC with AMD Duron 900 + Matrox GA400 graphics
Hmm... don't Matrox have their own binary driver somewhere?
3. PC with Athon XP 1800, running Xvnc 3.3.6. Viewed
across 100 Mbit
ethernet from vncviewer on Windows.
Machine 2 was the slowest at this task, so apparently there is no
hardware support for shading in the mga driver or the driver doesn't
like my hardware. Machine 2 does however run glxgears the fastest.
This tells me that your app doesn't use GLX, so it's probably doing all
the rendering using the machine's CPU, RAM, $deity knows what else. As
the Duron 900 is the slowest machine you've got.
I'm still boggled at anything over VNC being the fastest, though. That's
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