On Fri, Apr 22, 2016 at 11:28 PM, Nicolai Hähnle <nhaeh...@gmail.com> wrote: > On 22.04.2016 12:29, Nicolai Hähnle wrote: >> >> On 20.04.2016 23:02, Michel Dänzer wrote: >>> >>> On 21.04.2016 02:42, Marek Olšák wrote: >>>> >>>> On Thu, Apr 14, 2016 at 9:29 AM, Michel Dänzer <mic...@daenzer.net> >>>> wrote: >>>>> >>>>> On 14.04.2016 11:37, Michel Dänzer wrote: >>>>>> >>>>>> On 12.04.2016 21:33, Marek =?UNKNOWN?B?T2zFocOhaw==?= wrote: >>>>>>> >>>>>>> >>>>>>> URL: >>>>>>> >>>>>>> http://cgit.freedesktop.org/mesa/mesa/commit/?id=5a4b74d1ba2c156766a7a5dbfef099c7db5d6694 >>>>>>> >>>>>>> Author: Marek Olšák <marek.ol...@amd.com> >>>>>>> Date: Mon Apr 11 19:56:07 2016 +0200 >>>>>>> >>>>>>> gallium/radeon: relax requirements on VRAM placements on APUs >>>>>> >>>>>> >>>>>> This change caused a bunch of ARB_shader_load_image_store piglit tests >>>>>> to fail on my Kaveri, see some examples below. The incorrect values >>>>>> seem consistent. >>>>>> >>>>>> I suppose some buffers end up in GTT instead of VRAM with this >>>>>> change, but I'm not sure how that could cause problems. Any ideas? >>>>> >>>>> >>>>> Also, with the code modified to use GTT only for everything but >>>>> (potential) scanout buffers, the performance of Unigine Valley and the >>>>> Unreal Engine 4 Elemental demo is reduced by about 30%. So the premise >>>>> that GTT is about as fast as VRAM doesn't seem to hold true in practice >>>>> (at least with Kaveri and presumably other (pre-)CIK APUs; maybe it's >>>>> better with Carrizo and newer), which means that this change may cause >>>>> performance of long-running processes to drop significantly over time. >>>>> >>>>> Given all these issues, I'm afraid it may be better to revert this >>>>> change for now, until we have a better plan for dealing with this. >>>> >>>> >>>> Assuming you use the radeon kernel driver and you are not busy, would >>>> you please check whether the performance is lower on amdgpu as well? >>> >>> >>> I am using the radeon driver, but also quite busy. Nicolai, can you try >>> it on your Carrizo? >> >> >> I don't see any difference on Unigine Valley with my Carrizo (512MB of >> VRAM). > > > I have learned an important lesson today: the Phoronix Test Suite runner > eats my environment variables (and possibly babies?). So my earlier tests > were for nothing. > > In reality, Unigine Valley gains about 30% frame rate with the VRAM_GTT > placement.
It looks like we do need Kaveri results on amdgpu to know if CIK or radeon is the issue. Then, we can either turn it off for radeon or CIK. Marek _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
