performance problems with ATI Radeon r300
1i5t5.duncan at cox.net
Thu Jul 9 05:42:02 BST 2009
Felix Miata <mrmazda at earthlink.net> posted 4A4CD62A.2020908 at earthlink.net,
excerpted below, on Thu, 02 Jul 2009 11:45:46 -0400:
> I find this thread a bit hard to believe. Are there really people so
> naive as to believe a 5+ year old machine should be able to competently
> provide full KDE4 (Vista-style 3D) bling? I would expect only a
> Vista-competent (no more than ~9 months older than Vista) machine to
> produce acceptable KDE4 bling. My Radeon is rv380 (X600), and I wouldn't
> expect it to do well without all the bling turned off.
It should be able to do at least as well as the older KDE3 technology
does on the same hardware, with the same level of effects, on the same
Here, kde 3.5 (3.5.10) is my working desktop. kde 4.2 (4.2.4) is my
frustration desktop. One (but by no means the only one) of the reasons
is that 2-D only EXA accel, transparency-only effects (no fade, no drop-
shadow), are still so much slower than the exact same effects level on
kde 3.5 works with virtually no slow-down (as compared to no effects),
where on 4.2, it's slow and buggy, to the point kde tries to turn it off
General platform: Gentoo/~amd64, both kde 3.5.10 and 4.2.4 installed.
Older original dual socket Opteron 2xx style mobo (Tyan s2885), dual
maxed out 2.8 GHz dual-core Opteron 290 CPUs, 8 gigs RAM. 4-spindle SATA
based md/kernel RAID, RAID-6 main system, RAID-0 cache dirs, 4-way
striped swap, /tmp on tmpfs.
Specific to the issue here: Older r200 based Radeon 92xx (for many years,
the best graphics hardware one could buy to run with freedomware
drivers), running dual 1920x1200 LCDs stacked for 1920x2400. That's
critical, as either the card or the driver limits OpenGL to 2048x2048, so
the the bottom 352 px of the bottom monitor isn't OpenGL accelerated. As
a result, kde 4.2 won't enable OpenGL (even on the upper 2048 px)
effects. OK, I can accept that.
However, there are two specific issues:
1) KDE 4 provides no indication of what effects actually work with
XRender, and which require OpenGL. One would think they'd disable (dim
out and make them unselectable) the OpenGL required effects in XRender
mode, but they don't. Thus, one has to go trying each one to see if it
actually does what it says on the tin, and if it doesn't work, one is
still left wondering whether it's that it requires OpenGL, or whether
there's something else disabling it (maybe one hit the wrong keys trying
to invoke it, maybe it conflicts with another enabled effect, maybe kde
isn't seeing the key for some reason, etc).
This one is a major usability bug that frankly, should have been fixed
before a release the PR said was ready for the general public. It's easy
enough. KDE already detects whether the system can safely enable OpenGL
mode and disables it if it needs to. Why doesn't it disable OpenGL
requiring effects in the GUI at the same time? That's a beta level quirk
and I'm a power user that enjoys testing beta level software, but it
should have never made it into a release intended for general public
2) Even with the same effects settings as 3.5, kde 4.2 is DOG SLOW,
seconds to respond to active window changes, etc, where the response is
essentially instant in 3.5, to the point kde tries to disable the effects
Again, if it can be done in 3.5 without noticeable slowdowns at all (at
least with EXA enabled instead of XAA), what's the problem with 4.2? The
hardware is obviously capable, or I'd not have already been using the
exact same effects (transparency, no drop-shadows or fading) on kde 3.5
for years already!
And in 3.5, those effects were supposed to be bolted on and thus not
supposed to be at peak efficiency, while in 4.x, they're supposed to be
integrated, and therefore should run FASTER!
Anyway, I'll probably be upgrading to an r500 based card one of these
days. The board is late AGP with PCI-X, no PCI-E, so unfortunately the
cards cost more and the x1950 (rv570/r580) I'm looking at is still
running $150, unfortunately. And that's hard to come up with in this
economy. I may end up getting an earlier x1650 (rv530/rv560) instead,
for $70 or so IIRC. (The r5xx chips are the highest with full xorg/
kernel freedomware driver support ATM, the r6xx/r7xx chips are newer, but
don't have full xorg freedomware driver support yet, and the r5xx chips
are likely as good or better for AGP anyway, if they even have AGP based
r6xx/r7xx hd series cards at all.) KDE4 should work on them with full
OpenGL effects, which will be nice.
But that still doesn't answer the question of why if kde 3.5 can manage
an effect with virtually no slowdown, the same effect is dog slow on kde
4.2, or why the effects selection doesn't disable the opengl choices when
opengl is disabled. For this and other reasons, kde4 remains
"substantially broken" for my usage, at least thru 4.2.4, and my kde4
desktop remains my "frustration desktop" while my kde3 desktop is my
"working desktop". Oh, well...
Duncan - List replies preferred. No HTML msgs.
"Every nonfree program has a lord, a master --
and if you use the program, he is your master." Richard Stallman
This message is from the kde mailing list.
Account management: https://mail.kde.org/mailman/listinfo/kde.
More info: http://www.kde.org/faq.html.
More information about the kde