If there is a minimal performance oriented test of this function, I can ask the compiler team to study it w.r.t. unrolling heuristics.
Jeff On Wednesday, September 28, 2016, Barry Smith <bsm...@mcs.anl.gov> wrote: > > > Mr Hong Zhang has found that removing the manual unrolling from > MatMult_SeqAIJ_Inode() (at least with inode size 2) results in a good bump > in performance on KNL and pointed me to the Intel gospel > https://software.intel.com/en-us/articles/avoid-manual-loop-unrolling > which we've always ignored in the past. It would be good try the unrolled > and non-unrolled also on Xeon. > > We've never done a good job of managing our unrolling, where, how and > when we do it and macros for unrolling such as PetscSparseDensePlusDot. > Intel would say just throw it all away. > > Barry > > > > -- Jeff Hammond jeff.scie...@gmail.com http://jeffhammond.github.io/
