Hi. blender which built using a source file at the time of 467e12514e60 in CUDA8 has a shorter time required for rendering of BMW for around 20 seconds.
SHA-1-2f5db2e45b7a8af51b15c45bb41f5dcb49ae9d4d is slow. SHA-1-467e12514e60b4130cd0a33b59f53aa4cf7056b6 is fast. Windows 10 pro 64bits Intel i7 6700K 4.4GHz NVIDIA GTX 1070 MEMORY 16GB With best regards, PerfectionCat. ----- Original Message ----- >From: Sergey Sharybin <[email protected]> >To: Blender Developers <[email protected]> >Date: 2016/8/2, Tue 23:44 >Subject: Re: [Bf-committers] Cycles CUDA Toolkit 8 transition > >Hey again, > >Spent majority of the day trying to solve the regression, without much >success. Even simplest kernel needed for BMW scene is about 10% slower. >This is mainly coming from bump nodes. Enabling all other features makes >things even worse performance wise. > >I did some tweaks again to make sure all functions are inlined in the same >manner by CUDA 8.0 as they used to be before. So now PTax output shows >exactly same function, but for some reason spills are just higher with new >toolkit and at the same time stack usage is reasonably slower. Not sure yet >what's going on here and think we'd better leave this alone for until >official toolkit is released. > >For the time being i've switched buildbots to use more complicated setup, >using CUDA 7.5 for all kernels except sm_60 and sm_61 (new generation >cards) and using new toolkit only for new kernels. > >So hopefully now all maxwell and lower crads have same performance as >before. And yet users of new cards can have some degree of GPU rendering. > > >On Mon, Aug 1, 2016 at 6:15 PM, Sergey Sharybin <[email protected]> >wrote: > >> Hey everyone, >> >> In order to make Cycles officially support new Pascal cards (GTX 10x0) it >> is crucial to use CUDA Toolkit 8. While it is still in the RC stage we >> started looking into making it official one for Cycles. >> >> There is already some initial work done: >> >> - Tweaks are done to Cycles kernel to have same level of inlined functions >> (new toolkit barely used inlined functions, which resulted in poor >> performance on all cards) >> - New toolkit was installed onto all release environments and buildbots. >> >> So on a positive side, next buildbot's builds will support Pascal cards, >> yay! :) >> >> But unfortunately, while i've managed to keep Kepler cards (GTX760) same >> performance as before, we had a report from Jens in IRC about Maxwell cards >> having a poor performance yet again (in his case, up to 40% worse). >> >> This is really unacceptable, we'll keep working on solution for this >> issue. It might take some time, so just be aware and please be patient :) >> >> I will keep posted here with our progress. >> >> -- >> With best regards, Sergey Sharybin >> > > > >-- >With best regards, Sergey Sharybin >_______________________________________________ >Bf-committers mailing list >[email protected] >https://lists.blender.org/mailman/listinfo/bf-committers > > > _______________________________________________ Bf-committers mailing list [email protected] https://lists.blender.org/mailman/listinfo/bf-committers
