EXA problems on R420

[bitnick]

When I enable EXA in xorg.conf, certain things gets extremely slow - a simple thing like resizing gnome-terminal sized at about 80x25 takes over a second per window update! Let's not talk about rendering a 1000x1000 Firefox window... :(

At the same time, I can start compiz fine (although it takes quite some time to start), and things like wobbly windows are extremely smooth. Moving a window around in either compiz or Metacity is fast - but resizing, adding lines to the bottom of a gnome-terminal window, opening a window menu item etc. are all very, very slow, with 100 % cpu usage, in both Metacity and compiz.

I've read xorg.conf and radeon manual pages and tried every setting and combination of settings I can think of.

Is it only me that has this problem? What can be wrong?


I'm using the latest xf86-video-ati (checked out a few hours ago), "X Window System Version 1.3.0" (from Xorg.0.log), mesa-6.5.2-r1, xorg-server-1.3.0.0-r1, xorg-x11-7.2, libdrm-2.3.0 (from Gentoo equery).

[agd5f]

When I enable EXA in xorg.conf, certain things gets extremely slow - a simple thing like resizing gnome-terminal sized at about 80x25 takes over a second per window update! Let's not talk about rendering a 1000x1000 Firefox window... :(

At the same time, I can start compiz fine (although it takes quite some time to start), and things like wobbly windows are extremely smooth. Moving a window around in either compiz or Metacity is fast - but resizing, adding lines to the bottom of a gnome-terminal window, opening a window menu item etc. are all very, very slow, with 100 % cpu usage, in both Metacity and compiz.

I've read xorg.conf and radeon manual pages and tried every setting and combination of settings I can think of.

Is it only me that has this problem? What can be wrong?


EXA doesn't accelerate non-composited desktops well. Things will improve somewhat once support for blending is added to the r3x/r4xx render code.

[bitnick]

Thing is, I have the same problem under compiz (which is a composited desktop, right? :) ).

Everything that seems to involve drawing to a buffer (as opposed to moving it around or displaying it) is excruciatingly slow. (I mean, come on, almost 5 seconds to resize an empty gnome-terminal window under compiz?? I just timed it! It's considerably faster under Metacity, but still slow.)

If you tell me again this is the state of things I will believe you, though ;)

The parts I believe might be relevant from my xorg.conf:

Section "Module"
Load "dbe" # Double buffering extension
Load "extmod" # Misc server extensions
SubSection "extmod"
Option "omit xfree86-dga"
EndSubSection
Load "type1"
Load "freetype"
Load "dri"
Load "drm"
Load "glx"
EndSection

Section "dri"
Mode 0666
EndSection

Section "Extensions"
Option "Composite" "Enable"
EndSection

Section "Device"
Identifier "X800Pro-DVI"
Driver "radeon"
BusID "PCI:1:0:0"
Screen 0
Option "AccelMethod" "EXA"
Option "AGPMode" "4" # Need this with EXA. With "8" the desktop freezes quite often.
EndSection

[agd5f]

Thing is, I have the same problem under compiz (which is a composited desktop, right? :) ).

Everything that seems to involve drawing to a buffer (as opposed to moving it around or displaying it) is excruciatingly slow. (I mean, come on, almost 5 seconds to resize an empty gnome-terminal window under compiz?? I just timed it! It's considerably faster under Metacity, but still slow.)

If you tell me again this is the state of things I will believe you, though ;)


There's a reason XAA is still the default :)

[bitnick]

Hehe, ok :)

Thanks for taking the time to answer my questions!

[Bigon]

Setting Option "MigrationHeuristic" "greedy" makes everything run quite smoothly

[bitnick]

Setting Option "MigrationHeuristic" "greedy" makes everything run quite smoothly

I'm afraid it doesn't, no. :(

[agd5f]

Things should be improved in ati git. We've implemented support for blending, but now we are working on improving performance. Part of it is related to the driver (glyph performance still sucks), and part of it is due to bottlenecks in the core exa code in the xserver. Grabbing the latest radeon driver and xserver should help.

[bitnick]

Ok, I used mesa, kernel drm and xf86-video-ati from git, but xorg-server-1.3. So that may be it, then.

I don't really have the time to try a new xserver right now, but I am interested in the result if someone else that has experienced the same problem tries it.

[chrisr]

Things should be improved in ati git. We've implemented support for blending, but now we are working on improving performance.

Specifically:
https://bugs.freedesktop.org/show_bug.cgi?id=13258

This bug really worries me, because the program probably isn't that complex, yet the problem's effect is so obvious.

Of course, the problem might be in Mesa rather than the video driver. But then again, it might not.

[agd5f]

Specifically:
https://bugs.freedesktop.org/show_bug.cgi?id=13258

This bug really worries me, because the program probably isn't that complex, yet the problem's effect is so obvious.

Of course, the problem might be in Mesa rather than the video driver. But then again, it might not.

That's a problem in the r300 3D mesa driver, not the radeon ddx.

[bridgman]

There are probably all kinds of rendering problems in the 3d driver. We only released the 3D documentation for 3xx-5xx family parts in the last month or two, so the bugfixing spree has just started and will probably speed up once EXA has made more progress and more devs switch their attention from EXA to 3D.