<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">Hello,<div class="">I’m facing multiple issues with PCREDUNDANT and MATMPISBAIJ:</div><div style="orphans: 2; widows: 2;" class="">1) <a href="https://www.mcs.anl.gov/petsc/petsc-current/src/mat/impls/sbaij/mpi/mpisbaij.c.html#line3354" class="">https://www.mcs.anl.gov/petsc/petsc-current/src/mat/impls/sbaij/mpi/mpisbaij.c.html#line3354</a> shouldn’t this be <span style="orphans: 2; widows: 2;" class="">sum != N? I’m running an example where it says that sum (4) != Nbs (60), with a bs=15.</span></div><div style="orphans: 2; widows: 2;" class=""><span style="orphans: 2; widows: 2;" class="">2) when I’m using MATMPIBAIJ, I can do stuff like: </span>-prefix_mat_type baij -prefix_pc_type redundant -prefix_redundant_pc_type ilu, and in the KSPView, I have "package used to perform factorization: petsc”, so the underlying MatType is indeed MATSEQBAIJ.</div><div style="orphans: 2; widows: 2;" class="">However, with MATMPISBAIJ, if I do: -prefix_mat_type sbaij -prefix_pc_type redundant, first, it looks like you are hardwiring a PCLU (MatGetFactor() line 4440 in src/mat/interface/matrix.c Could not locate a solver package.), then, if I append -prefix_redundant_pc_type cholesky, I end up with an error related to MUMPS: MatGetFactor_sbaij_mumps() line 2625 in src/mat/impls/aij/mpi/mumps/mumps.c Cannot use PETSc SBAIJ matrices with block size > 1 with MUMPS Cholesky, use AIJ matrix instead. Why isn’t this call dispatched to PETSc Cholesky for SeqSBAIJ matrices?</div><div style="orphans: 2; widows: 2;" class=""><br class=""></div><div style="orphans: 2; widows: 2;" class="">Thanks,</div><div style="orphans: 2; widows: 2;" class="">Pierre</div><div style="orphans: 2; widows: 2;" class=""><br class=""></div><div style="orphans: 2; widows: 2;" class="">1) I don’t think this is tested right now, at least not in src/ksp/ksp/examples/tutorials</div><div style="orphans: 2; widows: 2;" class="">2) reproducer: src/ksp/ksp/examples/tutorials/ex2.c</div><div style="orphans: 2; widows: 2;" class="">$ mpirun -np 2 ./ex2 -pc_type redundant -mat_type sbaij</div><div style="orphans: 2; widows: 2;" class="">// error because trying to do LU with a symmetric matrix</div><div style="orphans: 2; widows: 2;" class="">$ mpirun -np 2 ./ex2 -pc_type redundant -mat_type sbaij -redundant_pc_type cholesky -ksp_view</div><div style="orphans: 2; widows: 2;" class="">// you’ll see: that MUMPS is being used, but since bs=1, it’s working, but it won’t for the general case</div><div style="orphans: 2; widows: 2;" class="">// the MatType is mpisbaij with "1 MPI processes" whereas with baij, it’s seqbaij</div><div style="orphans: 2; widows: 2;" class=""><br class=""></div></body></html>