spaffy/shoc — Issue #1: CUDA 4.1 FFT 50% Performance Drop
Author: spaffy
Created: 2012-02-29 21:50:02+00:00
State: open
Labels: bug

With the new LLVM compiler backend, CUDA FFT performance dropped by 50% on Keeneland. OpenCL performance stayed the same.

I suspect this might be due to loops being unrolled differently (the unroll option that used to go to the old compiler is now ignored).