[petsc-dev] SLEPc failure

[Franck Houssen]

I deal with domain decomposition. It was faster/easier to generate files with 1 proc: I guess the "dirichlet" and "neumann" matrices are the same in this case, so one get the same files in the end... I didn't realized that when I sent the files. My mistake.

At my side, when I use krylovschur, SLEPc fails using 1, 2, 4, 8, ... procs (each proc performs a SLEPc solve that may fail or not - difficult to catch one). For instance, I attached data of one failed domain out of 8 (8 MPI procs): matrices are very close but different. Moreover, I added EPS logs of the same run and domain but replacing krylovschur with arpack when SLEPc does not fail (regarding your remark that B could be indefinite, I added -mat_mumps_icntl_33 1 to get the determinant). 

Anyway, I don't expect you spend too much time on this. My understanding is that there is no way to relax this check ? Correct ?

Franck

----- Mail original -----
> De: "Jose E. Roman" <jroman at dsic.upv.es>
> À: "Franck Houssen" <franck.houssen at inria.fr>
> Cc: "For users of the development version of PETSc" <petsc-dev at mcs.anl.gov>
> Envoyé: Samedi 28 Octobre 2017 17:40:41
> Objet: Re: [petsc-dev] SLEPc failure
> 
> The two matrices are the same ...
> 
> > El 28 oct 2017, a las 13:11, Franck Houssen <franck.houssen at inria.fr>
> > escribió:
> > 
> > I just added that before EPSSetOperators:
> > PetscViewer viewerA;
> > PetscViewerBinaryOpen(PETSC_COMM_WORLD,"Atau.out",FILE_MODE_WRITE,&viewerA);
> > MatView(A,viewerA);
> > PetscViewer viewerB;
> > PetscViewerBinaryOpen(PETSC_COMM_WORLD,"Btau.out",FILE_MODE_WRITE,&viewerB);
> > MatView(B,viewerB);
> > 
> > At first, I avoided binary as I didn't know if the format handles
> > big/little endianness... So I prefered ASCII.
> > 
> > Binary data are attached.
> > 
> > Franck
> > 
> > PS : running debian with little endian.
> >>> python -c "import sys;print(0 if sys.byteorder=='big' else 1)"
> > 1
> > 
> > 
> > ----- Mail original -----
> >> De: "Jose E. Roman" <jroman at dsic.upv.es>
> >> À: "Franck Houssen" <franck.houssen at inria.fr>
> >> Cc: "For users of the development version of PETSc"
> >> <petsc-dev at mcs.anl.gov>
> >> Envoyé: Vendredi 27 Octobre 2017 18:52:56
> >> Objet: Re: [petsc-dev] SLEPc failure
> >> 
> >> I cannot load the files you sent. Please send the matrices in binary
> >> format.
> >> The easiest way is to run your program with -eps_view_mat0 binary:Atau.bin
> >> -eps_view_mat1 binary:Btau.bin
> >> 
> >> However, the files are written at the end of EPSSolve() so if the solve
> >> fails
> >> then it will not create the files. You can try running with -eps_max_it 1
> >> or add code in your main program to write the matrices.
> >> 
> >> Jose
> >> 
> >> 
> >>> El 27 oct 2017, a las 12:28, Franck Houssen <franck.houssen at inria.fr>
> >>> escribió:
> >>> 
> >>> Maybe could be convenient for the users to have an option (or an
> >>> EPSSetXXX)
> >>> to relax that check ?
> >>> Data are attached.
> >>> 
> >>> Franck
> >>> 
> >>> ----- Mail original -----
> >>>> De: "Jose E. Roman" <jroman at dsic.upv.es>
> >>>> À: "Franck Houssen" <franck.houssen at inria.fr>
> >>>> Cc: "For users of the development version of PETSc"
> >>>> <petsc-dev at mcs.anl.gov>
> >>>> Envoyé: Vendredi 27 Octobre 2017 10:15:44
> >>>> Objet: Re: [petsc-dev] SLEPc failure
> >>>> 
> >>>> There is no new option. What I mean is that from 3.7 to 3.8 we changed
> >>>> the
> >>>> line that produces this error. But it seems that it is still failing in
> >>>> your
> >>>> problem. Maybe your B matrix is indefinite or not exactly symmetric. Can
> >>>> you
> >>>> send me the matrices?
> >>>> Jose
> >>>> 
> >>>>> El 27 oct 2017, a las 9:57, Franck Houssen <franck.houssen at inria.fr>
> >>>>> escribió:
> >>>>> 
> >>>>> I use the development version (bitbucket clone). How to relax the check
> >>>>> ?
> >>>>> At command line option ?
> >>>>> 
> >>>>> Franck
> >>>>> 
> >>>>> ----- Mail original -----
> >>>>>> De: "Jose E. Roman" <jroman at dsic.upv.es>
> >>>>>> À: "Franck Houssen" <franck.houssen at inria.fr>
> >>>>>> Cc: "For users of the development version of PETSc"
> >>>>>> <petsc-dev at mcs.anl.gov>
> >>>>>> Envoyé: Jeudi 26 Octobre 2017 18:49:22
> >>>>>> Objet: Re: [petsc-dev] SLEPc failure
> >>>>>> 
> >>>>>> 
> >>>>>>> El 26 oct 2017, a las 18:36, Franck Houssen <franck.houssen at inria.fr>
> >>>>>>> escribió:
> >>>>>>> 
> >>>>>>> Here is a stack I end up with when trying to solve an eigen problem
> >>>>>>> (real,
> >>>>>>> sym, generalized) with SLEPc. My understanding is that, during the
> >>>>>>> Gram
> >>>>>>> Schmidt orthogonalisation, the projection of one basis vector turns
> >>>>>>> out
> >>>>>>> to
> >>>>>>> be null.
> >>>>>>> First, is this correct ? Second, in such cases, are there some
> >>>>>>> recommended
> >>>>>>> "recipe" to test/try (options) to get a clue on the problem ? (I
> >>>>>>> would
> >>>>>>> unfortunately perfectly understand the answer could be no !... As
> >>>>>>> this
> >>>>>>> totally depends on A/B).
> >>>>>>> 
> >>>>>>> With arpack, the eigen problem is solved (so the matrix A and B I use
> >>>>>>> seems
> >>>>>>> to be relevant). But, when I change from arpack to
> >>>>>>> krylovschur/ciss/arnoldi, I get the stack below.
> >>>>>>> 
> >>>>>>> Franck
> >>>>>>> 
> >>>>>>> [0]PETSC ERROR: #1 BV_SafeSqrt()
> >>>>>>> [0]PETSC ERROR: #2 BVNorm_Private()
> >>>>>>> [0]PETSC ERROR: #3 BVNormColumn()
> >>>>>>> [0]PETSC ERROR: #4 BV_NormVecOrColumn()
> >>>>>>> [0]PETSC ERROR: #5 BVOrthogonalizeCGS1()
> >>>>>>> [0]PETSC ERROR: #6 BVOrthogonalizeGS()
> >>>>>>> [0]PETSC ERROR: #7 BVOrthonormalizeColumn()
> >>>>>>> [0]PETSC ERROR: #8 EPSFullLanczos()
> >>>>>>> [0]PETSC ERROR: #9 EPSSolve_KrylovSchur_Symm()
> >>>>>>> [0]PETSC ERROR: #10 EPSSolve()
> >>>>>> 
> >>>>>> Is this with SLEPc 3.8? In SLEPc 3.8 we relaxed this check so I would
> >>>>>> suggest
> >>>>>> trying with it.
> >>>>>> Jose
> >>>>>> 
> >>>>>> 
> >>>> 
> >>>> 
> >>> <ABtau.tar.gz>
> >> 
> >> 
> > <ABtau.tar.gz>
> 
> 
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