[petsc-users] small dense solves

[Jed Brown]

On Mon, 21 Jun 2010 09:40:48 -0600 (MDT), Andrew T Barker <Andrew.Barker at Colorado.EDU> wrote:
> As one part of a larger parallel code, I want to do many small, dense,
> local linear solves.  Small means 6 by 6 or 9 by 9.  Building a KSP /
> Mat for this seems like overkill.

Definitely, it's also on the small size for LAPACK (assuming it's in a
very performance-sensitive place).  You could use src/mat/blockinvert.h
(provides unrolled versions used internally by MATBAIJ), C++ template
libraries (e.g. Eigen2) are also worth considering for small dense
linear algebra.

Jed