Barry Smith <bsm...@petsc.dev> writes: >> On Jan 25, 2022, at 11:55 AM, Jed Brown <j...@jedbrown.org> wrote: >> >> Barry Smith <bsm...@petsc.dev> writes: >> >>> Thanks Mark, far more interesting. I've improved the formatting to make it >>> easier to read (and fixed width font for email reading) >>> >>> * Can you do same run with say 10 iterations of Jacobi PC? >>> >>> * PCApply performance (looks like GAMG) is terrible! Problems too small? >> >> This is -pc_type jacobi. > > Dang, how come it doesn't warn about all the gamg arguments passed to the > program? I saw them and jump to the wrong conclusion.
We don't have -options_left by default. Mark has a big .petscrc or PETSC_OPTIONS. > How come PCApply is so low while Pointwise mult (which should be all of > PCApply) is high? I also think that's weird. >> >>> * VecScatter time is completely dominated by SFPack! Junchao what's up >>> with that? Lots of little kernels in the PCApply? PCJACOBI run will help >>> clarify where that is coming from. >> >> It's all in MatMult. >> >> I'd like to see a run that doesn't wait for the GPU. > > Indeed What is the command line option to turn PetscLogGpuTimeBegin/PetscLogGpuTimeEnd into a no-op even when -log_view is on? I know it'll mess up attribution, but it'll still tell us how long the solve took. Also, can we make WaitForKokkos a no-op? I don't think it's necessary for correctness (docs indicate kokkos::fence synchronizes).
