Alexander : petsc-mumps interface does not support MatMatSolve() see ~petsc/src/mat/impls/aij/mpi/mumps/mumps.c Likely MatMatSolve_Basic() is called which calls MatSolve() repeatedly, thus slow.
In addition, MUMPS only supports centralized rhs. Petsc interface must scatter distributed rhs into a seqential rhs vector for MUMPS. If num of rhs is large, would be slow here as well. The error in your report likely is a bug in petsc. I'm investigating it and will let you know once it is fixed. Hong On 13.08.2012 17:23, Hong Zhang wrote: > >> Alexander : >> Hmm, isrow is a matrix ordering, likely a bug :-( >> Can you send us a stand-alone code that reproduces this error? >> > > Hong, > > I can try to pull it out, but this may be tricky. > > > Do you use an external package for MatMatSolve()? >> > > Yes, MUMPS. > I use ksp with preonly. > > Originally I thought it will be faster to solve multiple problems using > MatMatSolve. > This turned out to be not true however, but the code is still like that. > > -- > Regards, > Alexander > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20120813/4fb4ee96/attachment.html>
