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AMD's open GPU documentation site
AMD's open GPU documentation site
Posted Feb 13, 2008 17:26 UTC (Wed) by jmayer (subscriber, #595)In reply to: AMD's open GPU documentation site by tajyrink
Parent article: AMD's open GPU documentation site
> XAA and EXA 2D accelerations are now already working on R500 Well, not really or not in the way most readers would expect: They have been implemented in the driver, so yes, they run, but currently run without any hardware support. This means that anyone running XAA or EXA get *less* performance than someone running just ShadowFB. See http://lists.opensuse.org/radeonhd/2008-01/msg00233.html for details.
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AMD's open GPU documentation site
Posted Feb 23, 2008 17:50 UTC (Sat) by daenzer (subscriber, #7050) [Link]
Where did you read 'without any hardware support' there? Both XAA and EXA would be totally pointless in that case of course. The benchmarks where they're slower than ShadowFB exercise paths that the driver doesn't accelerate yet (mostly related to the RENDER extension - that can be fixed now that AMD released 3D documentation), so the acceleration architectures have to pay a price for trying to accelerate things instead of just doing them with the CPU in system memory in the first place. It shouldn't be hard to find other benchmarks where hardware acceleration is much faster than ShadowFB. Which of the options works best in practice depends on the usage pattern, so everybody has to find out for themselves.