Pierre, Could the PETSc MUMPS interface "turn-off" ICNTL(6) in this situation so as to not trigger the confusing warning message from MUMPS?
Barry > On Nov 1, 2023, at 12:17 PM, Pierre Jolivet <[email protected]> wrote: > > > >> On 1 Nov 2023, at 3:33 PM, Zhang, Hong via petsc-users >> <[email protected]> wrote: >> >> Victoria, >> "** Maximum transversal (ICNTL(6)) not allowed because matrix is distributed >> Ordering based on METIS" > > This warning is benign and appears for every run using a sequential > partitioner in MUMPS with a MATMPIAIJ. > (I’m not saying switching to ParMETIS will not make the issue go away) > > Thanks, > Pierre > > $ ../../../../arch-darwin-c-debug-real/bin/mpirun -n 2 ./ex2 -pc_type lu > -mat_mumps_icntl_4 2 > Entering DMUMPS 5.6.2 from C interface with JOB, N = 1 56 > executing #MPI = 2, without OMP > > ================================================= > MUMPS compiled with option -Dmetis > MUMPS compiled with option -Dparmetis > MUMPS compiled with option -Dpord > MUMPS compiled with option -Dptscotch > MUMPS compiled with option -Dscotch > ================================================= > L U Solver for unsymmetric matrices > Type of parallelism: Working host > > ****** ANALYSIS STEP ******** > > ** Maximum transversal (ICNTL(6)) not allowed because matrix is distributed > Processing a graph of size: 56 with 194 edges > Ordering based on AMF > WARNING: Largest root node of size 26 not selected for parallel > execution > > Leaving analysis phase with ... > INFOG(1) = 0 > INFOG(2) = 0 > […] > >> Try parmetis. >> Hong >> From: petsc-users <[email protected]> on behalf of Victoria >> Rolandi <[email protected]> >> Sent: Tuesday, October 31, 2023 10:30 PM >> To: [email protected] <[email protected]> >> Subject: [petsc-users] Error using Metis with PETSc installed with MUMPS >> >> Hi, >> >> I'm solving a large sparse linear system in parallel and I am using PETSc >> with MUMPS. I am trying to test different options, like the ordering of the >> matrix. Everything works if I use the -mat_mumps_icntl_7 2 or >> -mat_mumps_icntl_7 0 options (with the first one, AMF, performing better >> than AMD), however when I test METIS -mat_mumps_icntl_7 5 I get an error >> (reported at the end of the email). >> >> I have configured PETSc with the following options: >> >> --with-cc=mpiicc --with-cxx=mpiicpc --with-fc=mpiifort >> --with-scalar-type=complex --with-debugging=0 --with-precision=single >> --download-mumps --download-scalapack --download-parmetis --download-metis >> >> and the installation didn't give any problems. >> >> Could you help me understand why metis is not working? >> >> Thank you in advance, >> Victoria >> >> Error: >> >> ****** ANALYSIS STEP ******** >> ** Maximum transversal (ICNTL(6)) not allowed because matrix is distributed >> Processing a graph of size: 699150 with 69238690 edges >> Ordering based on METIS >> 510522 37081376 [100] [10486 699150] >> Error! Unknown CType: -1 >
