benchmark more blas/lapack functions

[ev-br]

Currently we benchmark:

BLAS level 1

• ddot
• ?nrm2
• ?axpy

BLAS level 3

• ?gemm
• ?syrk

LAPACK:

• ?gesv (linalg.solve)
• ?gesdd (linalg.svd)
• ?syev (linalg.eigh)

---

@martin-frbg suggested it'd be useful to add

• ?gemv
• ?gbmv

for the banded matrix-vector multiply, what is more interesting to scale: matrix size or the number of bands?

---

• cdotc -- complex-valued BLAS level 1

[martin-frbg]

good question - maybe matrix size for now to keep it simple, although number of bands would also be interesting. GBMV is a curious case where the implementation is unchanged from the original GotoBLAS and may not have been evaluated for (multithreaded) performance at all.

[ev-br]

OK, gbmv benchmarks now run for a standard range of sizes from 100 to 1000 and kl=1, 2, 3 (kl=ku, so it's 3, 5, and 7 bands). Web display is at http://www.openmathlib.org/BLAS-Benchmarks/#benchmarks.gbmv.time_gbmv
and raw data is in the usual places from GH actions, https://github.com/OpenMathLib/BLAS-Benchmarks/actions/runs/9693385959/job/26748720100 for the graviton run etc.