[Bf-cycles] CUDA performance tests

[Brecht Van Lommel]

Hi all,

We're having some trouble with CUDA performance at the moment, with in
a performance regression on Titan cards compared to 2.69, and unclear
effects from recent changes. Further there's the new CUDA 6.0 toolkit,
which we ideally could move to, as sticking to 5.0 is a problem with
newer compilers.

We could use some help testing all this, especially for Titan cards as
I don't have one of those.


There's a google doc here:
https://docs.google.com/spreadsheets/d/1IKvO6s7h_0oVGbGE3giowx2fBvyXzIfdM3qCSfROJfI

For now I'm assuming someone with a Titan card can make own builds to
test these git revisions. If not we can build and upload binaries to
test.

The test is:
* download: http://www.pasteall.org/blend/28679
* run: ./blender -b modified_bmw.blend -f 1

If you've got a different .blend file that is giving performance
regressions, or you find different behavior when rendering in the UI
rather than command line, then results from that are welcome too.


The information that I'm looking for from this is especially:
* Which revision caused the Titan performance regressions?
* Is CUDA 6.0 performance acceptable to us for the next release?
* Were there significant performance regressions due to recent changes?
* Which effect do the two provided patches have when building with CUDA 6.0?

Thanks,
Brecht.