On 28/08/16 03:03 AM, Dieter Nützel wrote: > Am 25.08.2016 11:09, schrieb Michel Dänzer: >> On 24/08/16 06:35 AM, Eric Anholt wrote: >>> Michel Dänzer <mic...@daenzer.net> writes: >>>> On 20/08/16 04:42 AM, Eric Anholt wrote: >>>>> Michel Dänzer <mic...@daenzer.net> writes: >>>>> >>>>>> From: Michel Dänzer <michel.daen...@amd.com> >>>>>> >>>>>> Always use 3 buffers when flipping. With only 2 buffers, we have >>>>>> to wait >>>>>> for a flip to complete (which takes non-0 time even with asynchronous >>>>>> flips) before we can start working on the next frame. We were >>>>>> previously >>>>>> only using 2 buffers for flipping if the X server supports >>>>>> asynchronous >>>>>> flips, even when we're not using asynchronous flips. This could >>>>>> result >>>>>> in bad performance (the referenced bug report is an extreme case, >>>>>> where >>>>>> the inter-frame stalls were preventing the GPU from reaching its >>>>>> maximum >>>>>> clocks). >>>>>> >>>>>> I couldn't measure any performance boost using 4 buffers with >>>>>> flipping. >>>>>> Performance actually seemed to go down slightly, but that might have >>>>>> been just noise. >>>>>> >>>>>> Without flipping, a single back buffer is enough for swap interval 0, >>>>>> but we need to use 2 back buffers when the swap interval is non-0, >>>>>> otherwise we have to wait for the swap interval to pass before we can >>>>>> start working on the next frame. This condition was previously >>>>>> reversed. >>>>>> >>>>>> Cc: "12.0 11.2" <mesa-sta...@lists.freedesktop.org> >>>>>> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97260 >>>>>> Signed-off-by: Michel Dänzer <michel.daen...@amd.com> >>>>> >>>>> Reviewed-by: Eric Anholt <e...@anholt.net> >>>> >>>> Thanks. > > Hello Michel, > > found this _before_ your commit, but haven't had time, so... > > With this patch Blender at least 2.76b flicker horribly with > > 'User Preferences...' -> 'Window Draw Method: Automatic' > Switching to: > 'Window Draw Method: Tripple Buffer' > fix it. > > I'll add this to the related bug if you want.
It's a blender bug: https://bugs.freedesktop.org/show_bug.cgi?id=97059 -- Earthling Michel Dänzer | http://www.amd.com Libre software enthusiast | Mesa and X developer _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
