ATI Open vs. Closed AIGLX Performance

[ivanovic]

that's strange exa works way better for me on r300 card with opensource driver.did you use official driver or a git checkout? (i use the latter)

I am using the gentoo unstable default (beside the 2D driver for xorg). That is x11-drivers/xf86-video-ati-6.6.193, x11-base/x11-drm-20071019 and x11-libs/libdrm-2.3.0. As stated I do get exactly the same with fglrx when setting to exa.

The relevant part of my configuration:

Section "Device"
        Identifier      "ATI Graphics Adapter"
        Driver          "radeon"
        BusID           "PCI:1:0:0"
        Screen          0
        Option          "MonitorLayout"         "TMDS, NONE"
        Option          "AGPMode"               "8"
        Option          "RenderAccel"           "on"
#       Option          "AccelMethod"           "exa"
        Option          "GARTSize"              "128"
#       needed for tvtime
        Option          "XAANoOffscreenPixmaps" "true"
#       r300 driver options
        Option          "EnablePageFlip"        "true"
        Option          "ColorTiling"           "on"
#       fglrx options
        Option          "VideoOverlay"          "on"
        Option          "OpenGLOverlay"         "off"
        Option          "UseInternalAGPGART"    "no"
EndSection

Section "Screen"
        Identifier "Screen0"
        Device     "ATI Graphics Adapter"
        Monitor    "Dell2405FPW"
        DefaultDepth     24
EndSection

Section "DRI"
        Mode         0666
EndSection

Section "Extensions"
        Option "Composite" "Disable"
#       fglrx-only for xvideo (tvtime)
        Option "XVideo" "Enable"
EndSection

Section "ServerFlags"
        Option "AIGLX" "off"
EndSection

When removing the comment from "AccelMethod", things get really slow. Basically I do use the same config for both, fglrx and radeon (where fglrx has quite some more problems than the radeon driver...)

[cornelius]

Can Michael and others who get good Compiz desktop performance (not game fps) with 8.42.3 post their xorg.conf files? (or just the modification(s) done over the default) Was it just enabling EXA?

And compared to that, do those see any decrease in performance/responsiveness with the default xorg.conf settings?

[GhePeU]

To have meaningful results you must use xorg-server 1.4, mesa 7.0.1 and xf86-video-ati >=6.7.192 with EXA; this way you can benefit of the zero-copy-tfp work by Michael Daenzer, who improved radically compiz performances on r300-class hardware.
Repeat the tests with Fedora 8 when it'll be out, it should have everything is needed.

For xorg.conf I suggest:

    Driver      "radeon"
    Option      "RenderAccel"    "On"
    Option      "AccelMethod"    "exa"
    Option      "AccelDFS"       "On" 
    Option      "FBTexPercent"   "30"
    Option      "EnablePageFlip" "On"
    Option      "GARTSize"       "32"

RenderAccel is useless because it's not implemented yet in EXA but doesn't hurt.

EDIT:

PS.: xf86-video-ati = 2D driver, mesa = r300 3D driver, so if you're going to test fps in compiz or games you have to check the mesa release's version number.