MetalWalls
MetalWalls is a constant-potential electrochemical molecular-dynamics code (TIP4P / electrode capacitors). On the Orange Pi RV2 we A/B FFTW (LD_PRELOAD) and FlexiBLAS backends under one unchanged mw binary.
Benchmark source: opensolvers/benchmarks/metalwalls. Module: MetalWalls/21.06.1-foss-2023b on EESSI riscv.eessi.io 20240402.
Bottom line: on upstream
example/tip4p-water(215 molecules, no electrodes), FFT r5v ≈ 1.02× and BLAS backends ≈ 1.00×. Long-range Ewald/FFT is only ~11% of wall; Coulomb short-range (~50%) and vdW (~29%) dominate. Electrode capacitor examples deferred (too slow for a short A/B).
Profile (tip4p-water)
| Bucket | ≈ % wall |
|---|---|
| Coulomb short-range | ~50% |
| van der Waals | ~29% |
| Coulomb long-range (Ewald/FFT) | ~11% |
| RATTLE | ~7% |
Results (2026-08-21)
200 MD steps, mpirun -np 1. Temperatures match bit-for-bit across runs.
| Tag | Axis | Wall s |
|---|---|---|
| fft_scalar | LD_PRELOAD scalar libfftw3 |
41.27 |
| fft_r5v | LD_PRELOAD r5v libfftw3 |
40.59 (~1.02×) |
| blas_scalar | OPENBLAS_CORETYPE=RISCV64_GENERIC |
40.83 |
| blas_stock | default FlexiBLAS OpenBLAS | 40.53 |
| blas_patched | patched RVV OpenBLAS | 40.99 |
Measured: 2026-08-21 on Orange Pi RV2.