Gromacs on Ice Lake

GROMACS version: 2020.5
GROMACS modification: No
Anyone have advice for using Ice Lake processors with Gromacs? Especially using the latest OneAPI compiler and the latest MKL.

Hi David,

For any x86-based server the default configuration should do things right - provided you compile (actually: run CMake) on the same type of node as you’ll run on.

For Ice Lake, all processors should have dual AVX-512 units, which simplifies things a bit.

  1. You want to make sure you enable both AVX2 and AVX-512 in FFTW, or use the GROMACS option to download & build FFTW automatically.

  2. GROMACS should select an AVX-512 build by default, or use -DGMX_SIMD=AVX_512 if it doesn’t.

  3. You want to use the latest version of GROMACS (which is 2021, not 2020).

  4. If you want to play around with SYCL, use the master branch on GitLab, or try the SYCL-enabled version of 2021 which Alexey put on the website ( Downloads — GROMACS 2021-sycl documentation )

  5. Since we already provide hand-tuned AVX-512 kernels that are specifically designed for the SIMD width, “oneAPI” isn’t magically going to improve performance. SYCL is important, but the impact is mostly limited to Intel GPU hardware.