MODFLOW 6
MODFLOW 6 is a groundwater-flow model. On the Orange Pi RV2 the mf6 binary links PETSc → FlexiBLAS; we A/B OpenBLAS backends under one unchanged install.
Benchmark source: opensolvers/benchmarks/modflow. Module: MODFLOW/6.4.4-foss-2023b on EESSI riscv.eessi.io 20240402.
Change one variable. Same USGS example; only FlexiBLAS OpenBLAS differs.
Bottom line: patched vs scalar ≈ 1.00× (flat). This workload is not LAPACK-bound on the PETSc/IMS path exercised here. Head-file MD5s match across tags.
Workload
USGS example ex-gwf-lgrv-lgr (parent 25×90×78 + child 9×61×49) from modflow6-examples.
Run with mpirun -np 1 mf6 -p so the PETSc linear path is active (serial IMS without -p finishes the same model in ~54 s). A .petscrc requesting MUMPS LU was present but unused by MF6 6.4.4 (IMS shell PC).
Results (2026-08-21)
| Tag | Wall s | MF6 elapsed |
|---|---|---|
scalar (RISCV64_GENERIC) |
189.61 | 3:03.7 |
| stock | 189.00 | 3:03.4 |
| patched RVV | 189.98 | 3:04.3 |
Measured: 2026-08-21 on Orange Pi RV2.