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stepper infinite loop

Summary

When a NewtonLineSearchError occurs the same step size is repeated indefinitely

Steps to reproduce

Simulate brusselator example model in GUI (using membranes branch of dune-copasi)

What is the current bug behaviour?

Stuck in infinite loop

What is the expected correct behaviour?

Timestep should reduce, simulation should finish

Relevant logs, screenshots, files...?

Anything that helps reproducing the bug

Expand to see logs 
00:00:16.617 Increase factor: 1.5
00:00:16.617 Decrease factor: 0.5
00:00:16.617 Runge-Kutta method: alexander_2
00:00:16.617 Setting up time stepper
00:00:16.617 Stepper methd: Alexander (order 2)
00:00:16.617 Evolving system: 25.50s -> 26.00s
00:00:16.617 Trying step: 25.50s + 0.21s -> 25.71s
00:00:16.617 Get non-linear operator
00:00:16.618 Get one step operator
00:00:16.618 TIME STEP [Alexander (order 2)]      1 time (from):   2.5500e+01 dt:   2.0546e-01 time (to):   2.5705e+01
00:00:16.618 STAGE 1 time (to):   2.5560e+01.
00:00:16.643 === Dune::BiCGSTABSolver
00:00:16.644 === rate=2.217e-07, T=0.000998, TIT=inf, IT=0
00:00:16.659 === Dune::BiCGSTABSolver
00:00:16.661 === rate=3.776e-07, T=0.001888, TIT=0.001888, IT=1
00:00:16.675 === Dune::BiCGSTABSolver
00:00:16.676 === rate=7.807e-08, T=0.001001, TIT=inf, IT=0
00:00:16.682   Newton converged after  3 iterations.  Reduction:   5.9287e-11   (6.1181e-02s)
00:00:16.682 STAGE 2 time (to):   2.5705e+01.
00:00:16.703 === Dune::BiCGSTABSolver
00:00:16.704 === rate=2.378e-07, T=0.0009979, TIT=inf, IT=0
00:00:16.719 === Dune::BiCGSTABSolver
00:00:16.721 === rate=3.441e-07, T=0.001873, TIT=0.001873, IT=1
00:00:16.736 === Dune::BiCGSTABSolver
00:00:16.738 === rate=1.65e-07, T=0.00187, TIT=0.00187, IT=1
00:00:16.744   Newton converged after  3 iterations.  Reduction:   8.5140e-12   (5.5057e-02s)
00:00:16.744 ::: timesteps           1 (1)
00:00:16.744 ::: nl iterations       6 (6)
00:00:16.744 ::: lin iterations      3 (3)
00:00:16.744 ::: assemble time    5.0082e-02 (5.0082e-02)
00:00:16.744 ::: lin solve time   8.8332e-03 (8.8332e-03)
00:00:16.744 Time Step: 25.50s + 0.21s -> 25.71s
00:00:16.744 Stopped redirection of std::cout
00:00:16.744 Increasing step size: 0.21s -> 0.31s
00:00:16.744 Reduce step to match end time: 0.31s -> 0.29
00:00:16.744 Trying step: 25.71s + 0.29s -> 26.00s
00:00:16.744 TIME STEP [Alexander (order 2)]      2 time (from):   2.5705e+01 dt:   2.9454e-01 time (to):   2.6000e+01
00:00:16.744 STAGE 1 time (to):   2.5792e+01.
00:00:16.762 === Dune::BiCGSTABSolver
00:00:16.763 === rate=3.922e-07, T=0.001005, TIT=inf, IT=0
00:00:16.778 === Dune::BiCGSTABSolver
00:00:16.779 === rate=1.314e-07, T=0.0009983, TIT=inf, IT=0
00:00:16.793 === Dune::BiCGSTABSolver
00:00:16.795 === rate=4.439e-07, T=0.001902, TIT=0.001902, IT=1
00:00:16.801   Newton converged after  3 iterations.  Reduction:   2.3010e-09   (5.3757e-02s)
00:00:16.801 STAGE 2 time (to):   2.6000e+01.
00:00:16.823 === Dune::BiCGSTABSolver
00:00:16.824 === rate=4.643e-07, T=0.0009912, TIT=inf, IT=0
00:00:16.838 === Dune::BiCGSTABSolver
00:00:16.839 === rate=6.009e-07, T=0.001013, TIT=inf, IT=0
00:00:16.854 === Dune::BiCGSTABSolver
00:00:16.858 === rate=0.001523, T=0.003725, TIT=0.001863, IT=2
00:00:16.890 === Dune::BiCGSTABSolver
00:00:16.894 === rate=0.0009026, T=0.003671, TIT=0.001836, IT=2
00:00:16.952 === Dune::BiCGSTABSolver
00:00:16.956 === rate=0.004191, T=0.003662, TIT=0.001831, IT=2
00:00:17.024 Step failed (NewtonError)
00:00:17.024 NewtonLineSearchError [line_search:/home/lkeegan/install/dune/include/dune/pdelab/newton/newton.hh:703]: NewtonLineSearch::line_search(): line search failed, max iteration count reached, defect did not improve enough
00:00:17.024 Stopped redirection of std::cout
00:00:17.024 Trying step: 25.71s + 0.29s -> 26.00s
00:00:17.024 TIME STEP [Alexander (order 2)]      2 time (from):   2.5705e+01 dt:   2.9454e-01 time (to):   2.6000e+01
00:00:17.024 STAGE 1 time (to):   2.5792e+01.
00:00:17.042 === Dune::BiCGSTABSolver
00:00:17.043 === rate=3.922e-07, T=0.001016, TIT=inf, IT=0
00:00:17.058 === Dune::BiCGSTABSolver
00:00:17.059 === rate=1.314e-07, T=0.000987, TIT=inf, IT=0
00:00:17.073 === Dune::BiCGSTABSolver
00:00:17.075 === rate=4.439e-07, T=0.001888, TIT=0.001888, IT=1
00:00:17.081   Newton converged after  3 iterations.  Reduction:   2.3010e-09   (5.3635e-02s)
00:00:17.081 STAGE 2 time (to):   2.6000e+01.
00:00:17.102 === Dune::BiCGSTABSolver
00:00:17.103 === rate=4.643e-07, T=0.001001, TIT=inf, IT=0
00:00:17.118 === Dune::BiCGSTABSolver
00:00:17.119 === rate=6.009e-07, T=0.001005, TIT=inf, IT=0
00:00:17.134 === Dune::BiCGSTABSolver
00:00:17.137 === rate=0.001523, T=0.003684, TIT=0.001842, IT=2
00:00:17.170 === Dune::BiCGSTABSolver
00:00:17.174 === rate=0.0009026, T=0.003683, TIT=0.001841, IT=2
00:00:17.232 === Dune::BiCGSTABSolver
00:00:17.236 === rate=0.004191, T=0.003712, TIT=0.001856, IT=2
00:00:17.304 Step failed (NewtonError)
00:00:17.304 NewtonLineSearchError [line_search:/home/lkeegan/install/dune/include/dune/pdelab/newton/newton.hh:703]: NewtonLineSearch::line_search(): line search failed, max iteration count reached, defect did not improve enough
00:00:17.304 Stopped redirection of std::cout
00:00:17.304 Trying step: 25.71s + 0.29s -> 26.00s
00:00:17.304 TIME STEP [Alexander (order 2)]      2 time (from):   2.5705e+01 dt:   2.9454e-01 time (to):   2.6000e+01
00:00:17.304 STAGE 1 time (to):   2.5792e+01.
00:00:17.322 === Dune::BiCGSTABSolver
00:00:17.323 === rate=3.922e-07, T=0.0009902, TIT=inf, IT=0
00:00:17.338 === Dune::BiCGSTABSolver
00:00:17.339 === rate=1.314e-07, T=0.001004, TIT=inf, IT=0
00:00:17.353 === Dune::BiCGSTABSolver
00:00:17.355 === rate=4.439e-07, T=0.00188, TIT=0.00188, IT=1
00:00:17.361   Newton converged after  3 iterations.  Reduction:   2.3010e-09   (5.4121e-02s)
00:00:17.361 STAGE 2 time (to):   2.6000e+01.
00:00:17.382 === Dune::BiCGSTABSolver
00:00:17.383 === rate=4.643e-07, T=0.001016, TIT=inf, IT=0
00:00:17.398 === Dune::BiCGSTABSolver
00:00:17.399 === rate=6.009e-07, T=0.001008, TIT=inf, IT=0
00:00:17.414 === Dune::BiCGSTABSolver
00:00:17.417 === rate=0.001523, T=0.003659, TIT=0.001829, IT=2
00:00:17.450 === Dune::BiCGSTABSolver
00:00:17.454 === rate=0.0009026, T=0.003672, TIT=0.001836, IT=2
00:00:17.512 === Dune::BiCGSTABSolver
00:00:17.515 === rate=0.004191, T=0.00389, TIT=0.001945, IT=2
00:00:17.583 Step failed (NewtonError)
00:00:17.583 NewtonLineSearchError [line_search:/home/lkeegan/install/dune/include/dune/pdelab/newton/newton.hh:703]: NewtonLineSearch::line_search(): line search failed, max iteration count reached, defect did not improve enough
00:00:17.583 Stopped redirection of std::cout
00:00:17.583 Trying step: 25.71s + 0.29s -> 26.00s
00:00:17.583 TIME STEP [Alexander (order 2)]      2 time (from):   2.5705e+01 dt:   2.9454e-01 time (to):   2.6000e+01
00:00:17.583 STAGE 1 time (to):   2.5792e+01.
00:00:17.601 === Dune::BiCGSTABSolver
00:00:17.602 === rate=3.922e-07, T=0.001004, TIT=inf, IT=0
00:00:17.617 === Dune::BiCGSTABSolver
00:00:17.618 === rate=1.314e-07, T=0.001006, TIT=inf, IT=0
00:00:17.633 === Dune::BiCGSTABSolver
00:00:17.635 === rate=4.439e-07, T=0.001901, TIT=0.001901, IT=1
00:00:17.641   Newton converged after  3 iterations.  Reduction:   2.3010e-09   (5.4131e-02s)
00:00:17.641 STAGE 2 time (to):   2.6000e+01.
00:00:17.662 === Dune::BiCGSTABSolver
00:00:17.663 === rate=4.643e-07, T=0.0009904, TIT=inf, IT=0
00:00:17.677 === Dune::BiCGSTABSolver
00:00:17.678 === rate=6.009e-07, T=0.0009754, TIT=inf, IT=0
00:00:17.693 === Dune::BiCGSTABSolver
00:00:17.697 === rate=0.001523, T=0.003655, TIT=0.001827, IT=2
00:00:17.730 === Dune::BiCGSTABSolver
00:00:17.734 === rate=0.0009026, T=0.003729, TIT=0.001864, IT=2
00:00:17.791 === Dune::BiCGSTABSolver
00:00:17.795 === rate=0.004191, T=0.003691, TIT=0.001845, IT=2
00:00:17.863 Step failed (NewtonError)
00:00:17.863 NewtonLineSearchError [line_search:/home/lkeegan/install/dune/include/dune/pdelab/newton/newton.hh:703]: NewtonLineSearch::line_search(): line search failed, max iteration count reached, defect did not improve enough
00:00:17.863 Stopped redirection of std::cout
00:00:17.863 Trying step: 25.71s + 0.29s -> 26.00s

etc

Reproducing input

Do you have input files reproducing the problem? Insert them here:

Input data
Simulation Case Description goes here
GMSH grid file grid.msh
Run config file dune_compartment.ini

Ideas how to fix this?

I haven't looked at the changes in the stepper in detail, so not sure exactly what the problem is - but adding a test case where the timestep has to decrease for the simulation to run (like the attached model) might be a good idea.