[petsc-dev] TS code currently seems incompatible with geometric multigrid

[Barry Smith]

  SNES can work with geometric multigrid by constructing "smaller" Jacobians for the coarser levels on request (it uses the DMSNES infrastructure to handle this). This does not appear to be the case for TS where bad stuff happens. At some point it gets confused about the size of the Jacobians; something is likely wrong in the TS infrastructure ...

-pc_mg_galerkin does work since it creates the coarser matrices from R'AR product from the finest one.

~/Src/petsc/src/ts/examples/tutorials/advection-diffusion-reaction (barry/saws-options-merge-master=) arch-saws
$ ./ex5  -da_refine 1 -pc_type mg
[0]PETSC ERROR: --------------------- Error Message --------------------------------------------------------------
[0]PETSC ERROR: Nonconforming object sizes
[0]PETSC ERROR: Non conforming matrix add: 33800 8450 33800 8450
[0]PETSC ERROR: See http://www.mcs.anl.gov/petsc/documentation/faq.html for trouble shooting.
[0]PETSC ERROR: Petsc Development GIT revision: v3.5.3-1928-g2a409bb  GIT Date: 2015-02-15 15:20:55 -0600
[0]PETSC ERROR: ./ex5 on a arch-saws named Barrys-MacBook-Pro.local by barrysmith Sun Feb 15 21:20:50 2015
[0]PETSC ERROR: Configure options --download-mpich --download-saws PETSC_ARCH=arch-saws
[0]PETSC ERROR: #1 MatAXPY() line 35 in /Users/barrysmith/Src/PETSc/src/mat/utils/axpy.c
[0]PETSC ERROR: #2 TSComputeIJacobian() line 859 in /Users/barrysmith/Src/PETSc/src/ts/interface/ts.c
[0]PETSC ERROR: #3 SNESTSFormJacobian_ARKIMEX() line 1071 in /Users/barrysmith/Src/PETSc/src/ts/impls/arkimex/arkimex.c
[0]PETSC ERROR: #4 SNESTSFormJacobian() line 4170 in /Users/barrysmith/Src/PETSc/src/ts/interface/ts.c
[0]PETSC ERROR: #5 SNESComputeJacobian() line 2199 in /Users/barrysmith/Src/PETSc/src/snes/interface/snes.c
[0]PETSC ERROR: #6 KSPComputeOperators_SNES() line 531 in /Users/barrysmith/Src/PETSc/src/snes/interface/snes.c
[0]PETSC ERROR: #7 KSPSetUp() line 281 in /Users/barrysmith/Src/PETSc/src/ksp/ksp/interface/itfunc.c
[0]PETSC ERROR: #8 PCSetUp_MG() line 798 in /Users/barrysmith/Src/PETSc/src/ksp/pc/impls/mg/mg.c
[0]PETSC ERROR: #9 PCSetUp() line 918 in /Users/barrysmith/Src/PETSc/src/ksp/pc/interface/precon.c
[0]PETSC ERROR: #10 KSPSetUp() line 331 in /Users/barrysmith/Src/PETSc/src/ksp/ksp/interface/itfunc.c
[0]PETSC ERROR: #11 KSPSolve() line 528 in /Users/barrysmith/Src/PETSc/src/ksp/ksp/interface/itfunc.c
[0]PETSC ERROR: #12 SNESSolve_NEWTONLS() line 239 in /Users/barrysmith/Src/PETSc/src/snes/impls/ls/ls.c
[0]PETSC ERROR: #13 SNESSolve() line 3836 in /Users/barrysmith/Src/PETSc/src/snes/interface/snes.c
[0]PETSC ERROR: #14 TSStep_ARKIMEX() line 795 in /Users/barrysmith/Src/PETSc/src/ts/impls/arkimex/arkimex.c
[0]PETSC ERROR: #15 TSStep() line 3094 in /Users/barrysmith/Src/PETSc/src/ts/interface/ts.c
[0]PETSC ERROR: #16 TSSolve() line 3275 in /Users/barrysmith/Src/PETSc/src/ts/interface/ts.c
[0]PETSC ERROR: #17 main() line 116 in /Users/barrysmith/Src/petsc/src/ts/examples/tutorials/advection-diffusion-reaction/ex5.c
[0]PETSC ERROR: PETSc Option Table entries:
[0]PETSC ERROR: -da_refine 1
[0]PETSC ERROR: -malloc_test
[0]PETSC ERROR: -pc_type mg
[0]PETSC ERROR: ----------------End of Error Message -------send entire error message to petsc-maint at mcs.anl.gov----------
application called MPI_Abort(MPI_COMM_WORLD, 60) - process 0
[unset]: aborting job:
application called MPI_Abort(MPI_COMM_WORLD, 60) - process 0