Results 1 to 8 of 8

Thread: R300 Gallium3D Performance Is Topping Out

  1. #1
    Join Date
    Jan 2007
    Posts
    15,678

    Default R300 Gallium3D Performance Is Topping Out

    Phoronix: R300 Gallium3D Performance Is Topping Out

    Recently I showed benchmarks of the Radeon Gallium3D driver for a mature Radeon HD 4870 graphics card over the past two years to look at the performance improvements made to this open-source Linux graphics driver. Up today are benchmarks of an old Radeon X1950PRO (R500 class) ATI graphics card when using the original "R300g" Gallium3D driver and testing every major Mesa release going back to Mesa 7.8 with the classic R300 driver.

    http://www.phoronix.com/vr.php?view=17751

  2. #2
    Join Date
    Aug 2010
    Posts
    49

    Default warsow

    Does anyone know what the deal is with Warsow? Why is the classical driver almost 50% faster then gallium3d?

  3. #3
    Join Date
    Aug 2008
    Posts
    88

    Default

    Quote Originally Posted by wpoely86 View Post
    Does anyone know what the deal is with Warsow? Why is the classical driver almost 50% faster then gallium3d?
    Shaders not rendered correctly? Either way, that's what the tester should actually tell you.

    Edit: I mean, the tester should tell you or write the reason, why it is so. At least a little bit more than "seems to work better with classic driver". Otherwise benchmarking warsow makes no sense.
    Last edited by ChemicalBrother; 08-13-2012 at 10:51 AM.

  4. #4
    Join Date
    Nov 2008
    Location
    Madison, WI, USA
    Posts
    884

    Default

    Quote Originally Posted by ChemicalBrother View Post
    Shaders not rendered correctly? Either way, that's what the tester should actually tell you.

    Edit: I mean, the tester should tell you or write the reason, why it is so. At least a little bit more than "seems to work better with classic driver". Otherwise benchmarking warsow makes no sense.
    But at least we know that something is weird.

    Several possibilities:
    1) There's a hardware feature that R300c implements, but r300g doesn't (and hits a cpu fallback path).
    2) The gallium code is hitting a different (and possibly more complex) rendering path.
    3) There's a bottleneck in the gallium code.
    4) The classic driver could have had rendering glitches, which I'm assuming Michael would've mentioned... he usually does.

    So, if someone wants to do some more diagnostics, it might be good to grab an apitrace of Warsow running on the r300 classic driver, and then on the gallium driver. Try to play back the classic trace on both the classic and the gallium driver, and see what the comparative performance is. If the performance difference disappears during playback, then it's likely that Warsow chose a less complex rendering path for the classic driver. If there's still a performance difference, then someone will need to dig into the driver code to investigate.

  5. #5
    Join Date
    Oct 2007
    Location
    Toronto-ish
    Posts
    7,578

    Default

    Other possibility, I guess, is that 300g exposes a capability which 300c does not, Warsow uses that new capability, and the result is slower than not using it.

    Similar things happened around the transition to GL 2.x IIRC, particularly with id games.

  6. #6
    Join Date
    Aug 2007
    Location
    Poland
    Posts
    215

    Default

    And I'm wondering what was so special with Mesa 8.0.4 that it brought such big performance boost in Xonotic, while on Mesa 8.1-devel FPS goes back to the state of 7.11.2.
    Michael, do you have any lower end R300-R500 cards to test? And more tests with lower graphic resolution could say something more about performance.

  7. #7

    Default

    Lower FPS on a game may also be because of an optimization for another game. See for example this performance regression on 0 A.D. giving a performance improvement on Nexuiz.

  8. #8
    Join Date
    Aug 2012
    Posts
    315

    Default

    Quote Originally Posted by oibaf View Post
    Lower FPS on a game may also be because of an optimization for another game. See for example this performance regression on 0 A.D. giving a performance improvement on Nexuiz.
    We really need a PTS test-profile for 0 A.D. that game is worth the attention!

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •