[petsc-users] pcfieldsplit for a composite dm with multiple subfields

Gideon Simpson gideon.simpson at gmail.com
Wed Sep 9 13:48:36 CDT 2015 

So here’s one grid sequence with these solver flags:
-snes_max_it 100 -snes_converged_reason -snes_monitor \
-pc_type lu \
-pc_factor_mat_solver_package mumps -mat_mumps_icntl_28 1 -mat_mumps_icntl_7 6 \
-snes_max_funcs 500000 -snes_fd -snes_monitor -ksp_monitor_true_residual

By the way, the problem, I believe is approaching something that is singular, so it is not unreasonable to think there is some kind of inherent ill conditioning in the problem.

    0 SNES Function norm 2.977789375068e-12 
      0 KSP preconditioned resid norm 9.487609584353e-12 true resid norm 2.977789375068e-12 ||r(i)||/||b|| 1.000000000000e+00
      1 KSP preconditioned resid norm 3.713064216887e-24 true resid norm 9.247299640119e-23 ||r(i)||/||b|| 3.105424351885e-11
    1 SNES Function norm 2.511921299174e-12 
  Nonlinear solve converged due to CONVERGED_SNORM_RELATIVE iterations 1
  0 SNES Function norm 5.066222213175e+03 
    0 KSP preconditioned resid norm 3.135073899423e+01 true resid norm 5.066222213175e+03 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 4.667575811795e-11 true resid norm 2.582648659172e-07 ||r(i)||/||b|| 5.097780062738e-11
  1 SNES Function norm 8.484664416715e+02 
    0 KSP preconditioned resid norm 2.668033649331e+02 true resid norm 8.484664416715e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 3.096350794450e-10 true resid norm 1.126402252137e-08 ||r(i)||/||b|| 1.327574311505e-11
  2 SNES Function norm 6.549557200006e+02 
    0 KSP preconditioned resid norm 1.552337314505e+02 true resid norm 6.549557200006e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 1.781790941843e-09 true resid norm 5.596253874028e-08 ||r(i)||/||b|| 8.544476677024e-11
  3 SNES Function norm 5.770704424482e+02 
    0 KSP preconditioned resid norm 1.348464485234e+02 true resid norm 5.770704424482e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 1.909040505447e-10 true resid norm 6.992127254821e-09 ||r(i)||/||b|| 1.211659225719e-11
  4 SNES Function norm 5.237674957045e+02 
    0 KSP preconditioned resid norm 1.524393824592e+02 true resid norm 5.237674957045e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 1.664845931493e-10 true resid norm 5.713325641481e-09 ||r(i)||/||b|| 1.090813326206e-11
  5 SNES Function norm 4.753878819749e+02 
    0 KSP preconditioned resid norm 1.864281909532e+02 true resid norm 4.753878819749e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 1.409973828386e-10 true resid norm 4.289369979836e-09 ||r(i)||/||b|| 9.022884559061e-12
  6 SNES Function norm 4.221755368773e+02 
    0 KSP preconditioned resid norm 2.551073925659e+02 true resid norm 4.221755368773e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 5.540011959843e-10 true resid norm 1.441047729187e-08 ||r(i)||/||b|| 3.413385199545e-11
  7 SNES Function norm 3.806522663388e+02 
    0 KSP preconditioned resid norm 5.183358055470e+02 true resid norm 3.806522663388e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 2.063740790885e-09 true resid norm 3.530342872323e-08 ||r(i)||/||b|| 9.274456464634e-11
  8 SNES Function norm 3.762033603907e+02 
    0 KSP preconditioned resid norm 5.324397409227e+03 true resid norm 3.762033603907e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 6.352530213970e-09 true resid norm 9.590500220593e-08 ||r(i)||/||b|| 2.549286165502e-10
  9 SNES Function norm 3.758953286234e+02 
    0 KSP preconditioned resid norm 6.246847657999e+03 true resid norm 3.758953286234e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 5.367419000872e-08 true resid norm 8.213904234688e-07 ||r(i)||/||b|| 2.185157305564e-09
 10 SNES Function norm 3.756870388529e+02 
    0 KSP preconditioned resid norm 5.901626862375e+02 true resid norm 3.756870388529e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 1.330043229228e-09 true resid norm 1.418363475093e-08 ||r(i)||/||b|| 3.775385702481e-11
 11 SNES Function norm 3.728715884883e+02 
    0 KSP preconditioned resid norm 1.069749399855e+03 true resid norm 3.728715884883e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 2.911440821785e-10 true resid norm 9.552819316154e-09 ||r(i)||/||b|| 2.561959562241e-11
 12 SNES Function norm 3.722328158041e+02 
    0 KSP preconditioned resid norm 3.064673278570e+03 true resid norm 3.722328158041e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 1.105090853307e-08 true resid norm 1.085271466536e-07 ||r(i)||/||b|| 2.915571707969e-10
 13 SNES Function norm 3.720989356426e+02 
    0 KSP preconditioned resid norm 9.068377570178e+03 true resid norm 3.720989356426e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 3.784084466576e-08 true resid norm 3.777243066339e-07 ||r(i)||/||b|| 1.015117944322e-09
 14 SNES Function norm 3.720707403757e+02 
    0 KSP preconditioned resid norm 7.198056009453e+04 true resid norm 3.720707403757e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 7.120525808630e-08 true resid norm 1.054867000686e-06 ||r(i)||/||b|| 2.835124846476e-09
 15 SNES Function norm 3.720707293983e+02 
    0 KSP preconditioned resid norm 4.134314655599e+03 true resid norm 3.720707293983e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 2.003141582850e-08 true resid norm 2.046203596859e-07 ||r(i)||/||b|| 5.499501667784e-10
 16 SNES Function norm 3.719027845818e+02 
    0 KSP preconditioned resid norm 2.545115269075e+03 true resid norm 3.719027845818e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 4.965948884734e-08 true resid norm 5.071610656715e-07 ||r(i)||/||b|| 1.363692574235e-09
 17 SNES Function norm 3.714400762925e+02 
    0 KSP preconditioned resid norm 1.109601826815e+03 true resid norm 3.714400762925e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 6.169052076803e-09 true resid norm 6.563603648295e-08 ||r(i)||/||b|| 1.767069324832e-10
 18 SNES Function norm 3.701626928766e+02 
    0 KSP preconditioned resid norm 2.447547395077e+02 true resid norm 3.701626928766e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 1.250579098159e-09 true resid norm 1.218652092692e-08 ||r(i)||/||b|| 3.292206686799e-11
 19 SNES Function norm 3.556442798407e+02 
    0 KSP preconditioned resid norm 1.418496111605e+02 true resid norm 3.556442798407e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 3.627252384359e-10 true resid norm 1.951334080585e-09 ||r(i)||/||b|| 5.486757952241e-12
 20 SNES Function norm 3.496125058841e+02 
    0 KSP preconditioned resid norm 6.543042326746e+01 true resid norm 3.496125058841e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 1.377371559702e-10 true resid norm 1.295256556885e-09 ||r(i)||/||b|| 3.704834738706e-12
 21 SNES Function norm 3.146776071310e+02 
    0 KSP preconditioned resid norm 4.667517635820e+01 true resid norm 3.146776071310e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 2.743789267634e-09 true resid norm 1.644758285998e-08 ||r(i)||/||b|| 5.226804350630e-11
 22 SNES Function norm 2.855422195269e+02 
    0 KSP preconditioned resid norm 2.243742065865e+02 true resid norm 2.855422195269e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 1.047816533727e-10 true resid norm 2.299887594213e-09 ||r(i)||/||b|| 8.054457228859e-12
 23 SNES Function norm 2.806777486780e+02 
    0 KSP preconditioned resid norm 1.561899503179e+03 true resid norm 2.806777486780e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 3.972680147986e-09 true resid norm 7.239772649903e-08 ||r(i)||/||b|| 2.579389596790e-10
 24 SNES Function norm 2.805893466480e+02 
    0 KSP preconditioned resid norm 1.722111652119e+03 true resid norm 2.805893466480e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 5.170553469009e-09 true resid norm 6.273773919075e-08 ||r(i)||/||b|| 2.235927341513e-10
 25 SNES Function norm 2.805171735939e+02 
    0 KSP preconditioned resid norm 8.024869901472e+03 true resid norm 2.805171735939e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 2.741187759948e-08 true resid norm 3.211723859501e-07 ||r(i)||/||b|| 1.144929495173e-09
 26 SNES Function norm 2.805136061483e+02 
    0 KSP preconditioned resid norm 3.239737262200e+04 true resid norm 2.805136061483e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 2.317708795749e-08 true resid norm 3.672739850558e-07 ||r(i)||/||b|| 1.309291160949e-09
 27 SNES Function norm 2.805134008969e+02 
    0 KSP preconditioned resid norm 6.920567009699e+04 true resid norm 2.805134008969e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 1.101785240910e-07 true resid norm 1.523556762078e-06 ||r(i)||/||b|| 5.431315428092e-09
 28 SNES Function norm 2.805133530790e+02 
    0 KSP preconditioned resid norm 3.265182256725e+05 true resid norm 2.805133530790e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 3.903754744633e-07 true resid norm 6.654431764515e-06 ||r(i)||/||b|| 2.372233510980e-08
 29 SNES Function norm 2.805133509342e+02 
    0 KSP preconditioned resid norm 1.312587966212e+06 true resid norm 2.805133509342e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 1.990958223875e-07 true resid norm 1.311133369898e-05 ||r(i)||/||b|| 4.674049793106e-08
 30 SNES Function norm 2.805133508006e+02 
    0 KSP preconditioned resid norm 2.049236485623e+07 true resid norm 2.805133508006e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 3.432837714993e-05 true resid norm 4.348842776781e-04 ||r(i)||/||b|| 1.550315792232e-06
 31 SNES Function norm 2.805133508001e+02 
    0 KSP preconditioned resid norm 7.694877106483e+06 true resid norm 2.805133508001e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 4.401952388358e-06 true resid norm 1.008598135500e-04 ||r(i)||/||b|| 3.595544142990e-07
 32 SNES Function norm 2.805133507963e+02 
    0 KSP preconditioned resid norm 1.116553807875e+08 true resid norm 2.805133507963e+02 ||r(i)||/||b|| 1.000000000000e+00
    1 KSP preconditioned resid norm 7.718443445086e-06 true resid norm 1.327187421086e-03 ||r(i)||/||b|| 4.731280765492e-06
Nonlinear solve did not converge due to DIVERGED_LINE_SEARCH iterations 32

-gideon

> On Sep 9, 2015, at 1:52 PM, Barry Smith <bsmith at mcs.anl.gov> wrote:
> 
> 
>  Please run with the -snes_fd and one level of grid sequencing (where Newton was having trouble converging on the second level) with -snes_monitor -ksp_monitor_true_residual and send the output. Too much speculation and not enough data.
> 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20150909/3bebf5c4/attachment-0001.html>

More information about the petsc-users mailing list