Bug#909500: nvBLAS as an alternative to libblas.so.3

[Mo Zhou]

Package: libnvblas9.2
Version: 9.2.148-1
Severity: wishlist
X-Debbugs-CC: debian-science at lists.debian.org

Nvidia says nvBLAS is a "drop-in" BLAS library however it merely
provides several level-3 BLAS symbols. That being said, nvBLAS
is indeed a valid candidate for libblas.so.3 if explicitly specified
by the user.

The priority chain should look like this:

OpenBLAS (40) > BLIS (37) > Atlas (35) > Netlib (10) > MKL (1) > nvBLAS (-100)

- BLIS is still not avaialble in Debian.
- The fastest BLAS implementation MKL has priority 1 because it's non-free.
- nvBLAS has priority (-100) because (1) it's non-free (2) requires nvidia card
  (3) requires config file.

Apart from that, nvBLAS also needs an configuration file, unlike other blases.

I got a significant speed boost in octave following[2]. That means
to some extent nvBLAS should be added to the libblas.so.3 candidate
list. 
 
Reference:
[1] https://docs.nvidia.com/cuda/nvblas/index.html
[2] https://devblogs.nvidia.com/drop-in-acceleration-gnu-octave/