[petsc-dev] Recover from TS failure

Wed Nov 1 13:23:36 CDT 2017

Oh, Maybe the Jacobian has Nans or Infs even though the last time step
survived. Maybe it was going crazy. I'll check

On Wed, Nov 1, 2017 at 2:13 PM, Mark Adams <mfadams at lbl.gov> wrote:

> Yea, I don't understand the linear solve error:
>
> -ts_monitor -ts_type beuler -pc_type lu -pc_factor_mat_solver_package
> mumps -ksp_type preonly -snes_monitor -snes_rtol 1.e-10 -snes_stol 1.e-10
> -snes_converged_reason -snes_atol 1.e-18 -snes_converged_reason
>
> Maybe mumps?
>
> On Wed, Nov 1, 2017 at 2:02 PM, Jed Brown <jed at jedbrown.org> wrote:
>
>> Mark Adams <mfadams at lbl.gov> writes:
>>
>> > On Wed, Nov 1, 2017 at 1:46 PM, Jed Brown <jed at jedbrown.org> wrote:
>> >
>> >> Mark Adams <mfadams at lbl.gov> writes:
>> >>
>> >> > I have added some code in a TS post step method to look at the
>> number of
>> >> > nonlinear iterations and cut the time step if it took too many SNES
>> >> > iterations.  That helped but now I want to go one step further and
>> >> recover
>> >> > from a failed time step (see appended error message).
>> >> >
>> >> > How can/should I recover from a SNES failure inside of TS? I could
>> just
>> >> put
>> >> > TSSolve in a loop and if TS failed because of the solver, then
>> reduce the
>> >> > time step and try to recover the state, and try again.
>> >> >
>> >> > Thoughts?
>> >> >
>> >> > Thanks,
>> >> > Mark
>> >> >
>> >> > Note, this is a direct solver and the linear solver is diverging?
>> I've
>> >> > seen the same thing with the maximum its in SNES and failed
>> linesearch.
>> >> >
>> >> > 23 TS dt 0.0025 time 0.1025
>> >> >     0 SNES Function norm 9.997473571601e+04
>> >> >     1 SNES Function norm 2.295851692533e-01
>> >> >   Nonlinear solve did not converge due to DIVERGED_LINEAR_SOLVE
>> >> iterations 1
>> >> > [0]PETSC ERROR: --------------------- Error Message
>> >> > --------------------------------------------------------------
>> >> > [0]PETSC ERROR:
>> >> > [0]PETSC ERROR: TSStep has failed due to DIVERGED_NONLINEAR_SOLVE,
>> >> increase
>> >> > -ts_max_snes_failures or make negative to attempt recovery
>> >>
>> >> Did you increase -ts_max_snes_failures (TSSetMaxSNESFailures)?
>> >>
>> >
>> > Ah, read the error message :) with a negative value I get this.
>> >
>> > TS can not, or is not going to try, to reconstruct my state and reduce
>> the
>> > time step. So I think I need to do this myself.
>>
>> I don't understand.  Why is the linear solve diverging
>> (-ksp_converged_reason)?  What TS are you using?
>>
>> > I guess just making loop and testing in the TSConvergedReason, is the
>> way
>> > to go. We already do something like this for mesh adpativity.
>> >
>> > Thanks,
>> >
>> > 23 TS dt 0.0025 time 0.1025
>> >     0 SNES Function norm 9.997473571601e+04
>> >     1 SNES Function norm 2.295851692533e-01
>> >   Nonlinear solve did not converge due to DIVERGED_LINEAR_SOLVE
>> iterations 1
>> >     0 SNES Function norm 9.997473571601e+04
>> >   Nonlinear solve did not converge due to DIVERGED_LINEAR_SOLVE
>> iterations 0
>> >     0 SNES Function norm 9.997473571601e+04
>> >   Nonlinear solve did not converge due to DIVERGED_LINEAR_SOLVE
>> iterations 0
>> >     0 SNES Function norm 9.997473571601e+04
>> >   Nonlinear solve did not converge due to DIVERGED_LINEAR_SOLVE
>> iterations 0
>> >     0 SNES Function norm 9.997473571601e+04
>> >   Nonlinear solve did not converge due to DIVERGED_LINEAR_SOLVE
>> iterations 0
>> >     0 SNES Function norm 9.997473571601e+04
>> >   Nonlinear solve did not converge due to DIVERGED_LINEAR_SOLVE
>> iterations 0
>> >     0 SNES Function norm 9.997473571601e+04
>> >   Nonlinear solve did not converge due to DIVERGED_LINEAR_SOLVE
>> iterations 0
>> >     0 SNES Function norm 9.997473571601e+04
>> >   Nonlinear solve did not converge due to DIVERGED_LINEAR_SOLVE
>> iterations 0
>> >     0 SNES Function norm 9.997473571601e+04
>> >   Nonlinear solve did not converge due to DIVERGED_LINEAR_SOLVE
>> iterations 0
>> >     0 SNES Function norm 9.997473571601e+04
>> >   Nonlinear solve did not converge due to DIVERGED_LINEAR_SOLVE
>> iterations 0
>> >     0 SNES Function norm 9.997473571601e+04
>> >   Nonlinear solve did not converge due to DIVERGED_LINEAR_SOLVE
>> iterations 0
>> > [0]PETSC ERROR: --------------------- Error Message
>> > --------------------------------------------------------------
>> > [0]PETSC ERROR:
>> > [0]PETSC ERROR: TSStep has failed due to DIVERGED_STEP_REJECTED
>> > [0]PETSC ERROR: See http://www.mcs.anl.gov/petsc/documentation/faq.html
>> for
>> > trouble shooting.
>> > [0]PETSC ERROR: Petsc Development GIT revision: v3.8-53-ga2d93b2d43  GIT
>> > Date: 2017-10-09 12:56:49 -0400
>> > [0]PETSC ERROR: ./ex48 on a arch-macosx-gnu-O named MarksMac-5.local by
>> > markadams Wed Nov  1 13:51:24 2017
>> > [0]PETSC ERROR: Configure options --with-cc=clang --with-cc++=clang++
>> > COPTFLAGS="-O2 -g -mavx2" CXXOPTFLAGS="-O2 -g -mavx2" FOPTFLAGS="-O2 -g
>> > -mavx2" --download-mpich=1 --download-parmetis=1 --download-metis=1
>> > --download-hypre=1 --download-ml=1 --download-triangle=1
>> > --download-ctetgen=1 --download-p4est=1 --download-fftw
>> --download-mumps=1
>> > --download-scalapack=1 --with-x=0 --download-superlu_dist
>> > --download-superlu --download-ctetgen --with-debugging=0
>> --download-hdf5=1
>> > PETSC_ARCH=arch-macosx-gnu-O --download-chaco --with-viewfromoptions=1
>> > [0]PETSC ERROR: #1 TSStep() line 4130 in
>> > /Users/markadams/Codes/petsc/src/ts/interface/ts.c
>> > [0]PETSC ERROR: #2 TSSolve() line 4374 in
>> > /Users/markadams/Codes/petsc/src/ts/interface/ts.c
>> > *********** DIVERGED_STEP_REJECTED ierr=91 reason=-2
>> > L_2 Diff: 1.32241e+07 at time 0.1025
>> >
>> >
>> >
>> >
>> >>
>> >> > [0]PETSC ERROR: See http://www.mcs.anl.gov/petsc/d
>> ocumentation/faq.html
>> >> for
>> >> > trouble shooting.
>> >> > [0]PETSC ERROR: Petsc Development GIT revision: v3.8-53-ga2d93b2d43
>> GIT
>> >> > Date: 2017-10-09 12:56:49 -0400
>> >> > [0]PETSC ERROR: ./ex48 on a arch-macosx-gnu-O named MarksMac-5.local
>> by
>> >> > markadams Wed Nov  1 13:17:15 2017
>> >> > [0]PETSC ERROR: Configure options --with-cc=clang --with-cc++=clang++
>> >> > COPTFLAGS="-O2 -g -mavx2" CXXOPTFLAGS="-O2 -g -mavx2" FOPTFLAGS="-O2
>> -g
>> >> > -mavx2" --download-mpich=1 --download-parmetis=1 --download-metis=1
>> >> > --download-hypre=1 --download-ml=1 --download-triangle=1
>> >> > --download-ctetgen=1 --download-p4est=1 --download-fftw
>> >> --download-mumps=1
>> >> > --download-scalapack=1 --with-x=0 --download-superlu_dist
>> >> > --download-superlu --download-ctetgen --with-debugging=0
>> >> --download-hdf5=1
>> >> > PETSC_ARCH=arch-macosx-gnu-O --download-chaco
>> --with-viewfromoptions=1
>> >> > [0]PETSC ERROR: #1 TSStep() line 4129 in
>> >> > /Users/markadams/Codes/petsc/src/ts/interface/ts.c
>> >> > [0]PETSC ERROR: #2 TSSolve() line 4374 in
>> >> > /Users/markadams/Codes/petsc/src/ts/interface/ts.c
>> >> > [0]PETSC ERROR: #3 main() line 1161 in /Users/markadams/Codes/mhd/
>> >> src/ex48.c
>> >>
>>
>
>
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