Re: [petsc-users] GAMG for the unsymmetrical matrix

On Sun, Apr 9, 2017 at 6:04 AM, Mark Adams wrote: > You seem to have two levels here and 3M eqs on the fine grid and 37 on > the coarse grid. I don't understand that. > > You are also calling the AMG setup a lot, but not spending much time > in it. Try running with -info and

Re: [petsc-users] GAMG for the unsymmetrical matrix

Hi Mark, Thanks for your reply. On Wed, Apr 12, 2017 at 9:16 AM, Mark Adams wrote: > The problem comes from setting the number of MG levels (-pc_mg_levels 2). > Not your fault, it looks like the GAMG logic is faulty, in your version at > least. > What I want is that GAMG

Re: [petsc-users] how to use petsc4py with mpi subcommunicators?

Thanks, Gaetan, for your suggestions and for running the code…Now I know for sure there is something wrong with my installation! Cheers Rodrigo From: Gaetan Kenway [mailto:gaet...@gmail.com] Sent: Wednesday, April 12, 2017 12:20 PM To: Rodrigo Felicio Cc: petsc-users@mcs.anl.gov Subject: Re:

Re: [petsc-users] how to use petsc4py with mpi subcommunicators?

Maybe try doing pComm=MPI.COMM_WORLD instead of the PETSc.COMM_WORLD. I know it shouldn't matter, but it's worth a shot. Also then you won't need the tompi4py() i guess. Gaetan On Wed, Apr 12, 2017 at 10:17 AM, Gaetan Kenway wrote: > Hi Rodrigo > > I just ran your example on

Re: [petsc-users] how to use petsc4py with mpi subcommunicators?

Hi Rodrigo I just ran your example on Nasa's Pleiades system. Here's what I got: PBS r459i4n11:~> time mpiexec -n 5 python3.5 another_split_ex.py number of subcomms = 2.5 petsc rank=2, petsc size=5 sub rank 1/3, color:0 petsc rank=4, petsc size=5 sub rank 2/3, color:0 petsc rank=0, petsc size=5

Re: [petsc-users] how to use petsc4py with mpi subcommunicators?

Going over my older codes I found out that I have already tried the approach of splitting PETSc.COMM_WORLD, but whenever I try to create a matrix using a subcommuicator, the program fails. For example, executing the following python code attached to this msg, I get the following output time

Re: [petsc-users] how to use petsc4py with mpi subcommunicators?

One other quick note: Sometimes it appears that mpi4py for petsc4py do not always play nicely together. I think you want to do the petsc4py import first and then the mpi4py import. Then you can split the MPI.COMM_WORLD all you want and create any petsc4py objects on them. Or if that doesn't

[petsc-users] dmplex face normals orientation

Hello, I have problems determining the orientation of the face normals of a DMPlex. I create a DMPlex, for example with DMPlexCreateHexBoxMesh(). Next, I get the face normals using DMPlexComputeGeometryFVM(DM dm, Vec *cellgeom, Vec *facegeom). facegeom gives the correct normals, but I don't know

Re: [petsc-users] GAMG for the unsymmetrical matrix

The problem comes from setting the number of MG levels (-pc_mg_levels 2). Not your fault, it looks like the GAMG logic is faulty, in your version at least. GAMG will force the coarsest grid to one processor by default, in newer versions. You can override the default with:

Re: [petsc-users] how to use petsc4py with mpi subcommunicators?

Thanks Jed and Gaetan. I will try that approach of splitting PETSc.COMM_WORLD, but I still need to load mpi4py (probably after PETSc), because PETSc.Comm is very limited, i.e., it does not have the split function, for example. My goal is to be able to set different matrices and vectors for

[petsc-users] -log_summary: User Manual outdated

pp. 174, 183 in the current User Manual describe option -log_summary. Running code with this option yields WARNING: -log_summary is being deprecated; switch to -log_view Btw either form of the option is missing in the Index. smime.p7s Description: S/MIME Cryptographic Signature