Mark, I've run GAMG twice with different coarse grid sizes of 2 and 8 with 1 sweep of SOR on the coarse grid. For a size of 8 it converges nicely, but for a size of 2, I think the null space is causing too many problems. If GAMG were to coarsen to a size of 1, then there would be no hope because only the null space would remain, right? This doesn't ever seem to occur with ML because there are at least as many rows as processors.
John On Fri, Mar 30, 2012 at 8:42 AM, Mark F. Adams <mark.adams at columbia.edu>wrote: > > On Mar 29, 2012, at 2:40 PM, John Mousel wrote: > > I'm attempting to solve a non-symmetric discretization of a 3D Poisson > problem. The problem is singular. I've attached the results of KSPView from > runs with ML and GAMG. When I run ML, I get convergence in 30 iterations. > When I attempt to use the same settings with GAMG, I'm not getting > convergence at all. The two things I notice are: > > 1. GAMG is using KSPType preonly, even though I've set it to be Richardson > in my command line options. > > > PETSc seems to switch the coarse grid solver to GMRES in Setup. This > seems to be a bug and I unwisely decide to override this manually. I will > undo this in the next checkin. This should not be the problem however. > > 2. ML only coarsens down to 4 rows while GAMG coarsens to 2. My problem is > singular, and whenever I try to use LU, I get zero pivot problems. To > mitigate this, I've been using Richardson with SOR on the coarse matrix. > Could the smaller coarse grid size of GAMG be causing problems with SOR. If > so, is there a way to put a lower limit on the coarse grid size? > > > I'm thinking that with a 2x2 coarse grid 8 iterations of SOR is picking up > the null space. Maybe try just one SOR iteration on the coarse grid. > > Also, can you run with options_left so that I can see your arguments. One > known bug is the mat_diagaonal_scale breaks GAMG, but it should also break > ML. > > Mark > > John > > On Thu, Mar 29, 2012 at 11:03 AM, Jed Brown <jedbrown at mcs.anl.gov> wrote: > >> On Thu, Mar 29, 2012 at 09:18, John Mousel <john.mousel at gmail.com> wrote: >> >>> [0]PETSC ERROR: Error in external library! >>> [0]PETSC ERROR: Cannot disable floating point exceptions! >>> >> >> Looks like something is strange with your environment because fesetenv() >> is returning an error. I have disabled the call if the trap mode is not >> changing. >> >> http://petsc.cs.iit.edu/petsc/petsc-dev/rev/352b4c19e451 >> > > <KSPView_GAMG.txt><KSPView_ML.txt> > > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20120330/f464616b/attachment-0001.htm> -------------- next part -------------- Residual norms for pres_ solve. 0 KSP preconditioned resid norm 5.016797113851e+03 true resid norm 1.537048121012e+01 ||r(i)||/||b|| 1.000000000000e+00 2 KSP preconditioned resid norm 2.593195031348e+03 true resid norm 1.577483110619e+02 ||r(i)||/||b|| 1.026306911966e+01 4 KSP preconditioned resid norm 4.642597221361e+02 true resid norm 3.165516339207e+01 ||r(i)||/||b|| 2.059477706608e+00 6 KSP preconditioned resid norm 1.121148735724e+02 true resid norm 1.634561891940e+01 ||r(i)||/||b|| 1.063442236840e+00 8 KSP preconditioned resid norm 4.092437868938e+02 true resid norm 4.290066631217e+01 ||r(i)||/||b|| 2.791107560375e+00 10 KSP preconditioned resid norm 2.364490073524e+01 true resid norm 9.278095018184e-01 ||r(i)||/||b|| 6.036307446299e-02 12 KSP preconditioned resid norm 1.118938046010e+01 true resid norm 8.235420783716e-01 ||r(i)||/||b|| 5.357945968727e-02 14 KSP preconditioned resid norm 8.827495203651e-01 true resid norm 1.253023900141e-02 ||r(i)||/||b|| 8.152144900421e-04 16 KSP preconditioned resid norm 5.786122993849e-02 true resid norm 2.785770732954e-03 ||r(i)||/||b|| 1.812416081755e-04 18 KSP preconditioned resid norm 1.482851639037e-02 true resid norm 7.572356321341e-04 ||r(i)||/||b|| 4.926557742613e-05 20 KSP preconditioned resid norm 2.833429772564e-02 true resid norm 4.152766547014e-04 ||r(i)||/||b|| 2.701780438911e-05 22 KSP preconditioned resid norm 2.727719252108e-03 true resid norm 1.753161236491e-04 ||r(i)||/||b|| 1.140602699762e-05 24 KSP preconditioned resid norm 5.417522429762e-05 true resid norm 1.308360805994e-05 ||r(i)||/||b|| 8.512165547116e-07 26 KSP preconditioned resid norm 1.274290782774e-05 true resid norm 1.317046021128e-05 ||r(i)||/||b|| 8.568671358587e-07 KSP Object:(pres_) 4 MPI processes type: bcgsl BCGSL: Ell = 2 BCGSL: Delta = 0 maximum iterations=1000 tolerances: relative=1e-08, absolute=1e-50, divergence=10000 left preconditioning has attached null space using nonzero initial guess using PRECONDITIONED norm type for convergence test PC Object:(pres_) 4 MPI processes type: ml MG: type is MULTIPLICATIVE, levels=6 cycles=v Cycles per PCApply=1 Using Galerkin computed coarse grid matrices Coarse grid solver -- level ------------------------------- KSP Object: (pres_mg_coarse_) 4 MPI processes type: richardson Richardson: damping factor=1 maximum iterations=1, initial guess is zero tolerances: relative=1e-05, absolute=1e-50, divergence=10000 left preconditioning using PRECONDITIONED norm type for convergence test PC Object: (pres_mg_coarse_) 4 MPI processes type: sor SOR: type = local_symmetric, iterations = 8, local iterations = 1, omega = 1 linear system matrix = precond matrix: Matrix Object: 4 MPI processes type: mpiaij rows=4, cols=4 total: nonzeros=16, allocated nonzeros=16 total number of mallocs used during MatSetValues calls =0 not using I-node (on process 0) routines Down solver (pre-smoother) on level 1 ------------------------------- KSP Object: (pres_mg_levels_1_) 4 MPI processes type: richardson Richardson: damping factor=1 maximum iterations=1 tolerances: relative=1e-05, absolute=1e-50, divergence=10000 left preconditioning using nonzero initial guess using PRECONDITIONED norm type for convergence test PC Object: (pres_mg_levels_1_) 4 MPI processes type: sor SOR: type = local_symmetric, iterations = 1, local iterations = 1, omega = 1 linear system matrix = precond matrix: Matrix Object: 4 MPI processes type: mpiaij rows=7, cols=7 total: nonzeros=39, allocated nonzeros=39 total number of mallocs used during MatSetValues calls =0 using I-node (on process 0) routines: found 1 nodes, limit used is 5 Up solver (post-smoother) same as down solver (pre-smoother) Down solver (pre-smoother) on level 2 ------------------------------- KSP Object: (pres_mg_levels_2_) 4 MPI processes type: richardson Richardson: damping factor=1 maximum iterations=1 tolerances: relative=1e-05, absolute=1e-50, divergence=10000 left preconditioning using nonzero initial guess using PRECONDITIONED norm type for convergence test PC Object: (pres_mg_levels_2_) 4 MPI processes type: sor SOR: type = local_symmetric, iterations = 1, local iterations = 1, omega = 1 linear system matrix = precond matrix: Matrix Object: 4 MPI processes type: mpiaij rows=78, cols=78 total: nonzeros=2914, allocated nonzeros=2914 total number of mallocs used during MatSetValues calls =0 using I-node (on process 0) routines: found 4 nodes, limit used is 5 Up solver (post-smoother) same as down solver (pre-smoother) Down solver (pre-smoother) on level 3 ------------------------------- KSP Object: (pres_mg_levels_3_) 4 MPI processes type: richardson Richardson: damping factor=1 maximum iterations=1 tolerances: relative=1e-05, absolute=1e-50, divergence=10000 left preconditioning using nonzero initial guess using PRECONDITIONED norm type for convergence test PC Object: (pres_mg_levels_3_) 4 MPI processes type: sor SOR: type = local_symmetric, iterations = 1, local iterations = 1, omega = 1 linear system matrix = precond matrix: Matrix Object: 4 MPI processes type: mpiaij rows=889, cols=889 total: nonzeros=75418, allocated nonzeros=75418 total number of mallocs used during MatSetValues calls =0 not using I-node (on process 0) routines Up solver (post-smoother) same as down solver (pre-smoother) Down solver (pre-smoother) on level 4 ------------------------------- KSP Object: (pres_mg_levels_4_) 4 MPI processes type: richardson Richardson: damping factor=1 maximum iterations=1 tolerances: relative=1e-05, absolute=1e-50, divergence=10000 left preconditioning using nonzero initial guess using PRECONDITIONED norm type for convergence test PC Object: (pres_mg_levels_4_) 4 MPI processes type: sor SOR: type = local_symmetric, iterations = 1, local iterations = 1, omega = 1 linear system matrix = precond matrix: Matrix Object: 4 MPI processes type: mpiaij rows=16562, cols=16562 total: nonzeros=1527407, allocated nonzeros=1527407 total number of mallocs used during MatSetValues calls =0 not using I-node (on process 0) routines Up solver (post-smoother) same as down solver (pre-smoother) Down solver (pre-smoother) on level 5 ------------------------------- KSP Object: (pres_mg_levels_5_) 4 MPI processes type: richardson Richardson: damping factor=1 maximum iterations=1 tolerances: relative=1e-05, absolute=1e-50, divergence=10000 left preconditioning has attached null space using nonzero initial guess using PRECONDITIONED norm type for convergence test PC Object: (pres_mg_levels_5_) 4 MPI processes type: sor SOR: type = local_symmetric, iterations = 1, local iterations = 1, omega = 1 linear system matrix = precond matrix: Matrix Object: 4 MPI processes type: mpiaij rows=178085, cols=178085 total: nonzeros=4676387, allocated nonzeros=8374105 total number of mallocs used during MatSetValues calls =0 not using I-node (on process 0) routines Up solver (post-smoother) same as down solver (pre-smoother) linear system matrix = precond matrix: Matrix Object: 4 MPI processes type: mpiaij rows=178085, cols=178085 total: nonzeros=4676387, allocated nonzeros=8374105 total number of mallocs used during MatSetValues calls =0 not using I-node (on process 0) routines WARNING! There are options you set that were not used! WARNING! could be spelling mistake, etc! Option left: name:-pres_options_left no value Options: -pres_ksp_type bcgsl -pres_pc_type ml -pres_pc_ml_Threshold .01 -pres_mg_coarse_ksp_type richardson -pres_mg_coarse_pc_type sor -pres_mg_coarse_pc_sor_its 8 -pres_ksp_monitor_true_residual -pres_ksp_view -pres_options_left -------------- next part -------------- RUN 1: Options: -pres_ksp_type bcgsl -pres_pc_type gamg -pres_pc_gamg_sym_graph -pres_pc_gamg_coarse_eq_limit 2 -pres_pc_gamg_agg_nsmooths 1 -pres_pc_gamg_threshold 0.01 -pres_mg_levels_ksp_type richardson -pres_mg_levels_pc_type sor -pres_mg_coarse_ksp_type richardson -pres_mg_coarse_pc_type sor -pres_mg_coarse_pc_sor_its 1 -pres_ksp_monitor_true_residual -pres_pc_gamg_verbose 2 -pres_ksp_view -pres_options_left [0]PCSetFromOptions_GAMG threshold set 1.000000e-02 [0]PCSetUp_GAMG level 0 N=178085, n data rows=1, n data cols=1, nnz/row (ave)=26, np=4 [0]PCGAMGFilterGraph 64.0278% nnz after filtering, with threshold 0.01, 26.2593 nnz ave. [0]maxIndSetAgg removed 0 of 178085 vertices. (0 local) 6937 selected. [0]PCGAMGProlongator_AGG New grid 6937 nodes PCGAMGOptprol_AGG smooth P0: max eigen=1.927344e+00 min=4.441888e-02 PC=jacobi [0]PCSetUp_GAMG 1) N=6937, n data cols=1, nnz/row (ave)=63, 4 active pes [0]PCGAMGFilterGraph 32.3853% nnz after filtering, with threshold 0.01, 63.4622 nnz ave. [0]maxIndSetAgg removed 0 of 6937 vertices. (0 local) 167 selected. [0]PCGAMGProlongator_AGG New grid 167 nodes PCGAMGOptprol_AGG smooth P0: max eigen=4.364217e+00 min=5.712156e-03 PC=jacobi [0]createLevel aggregate processors: npe: 4 --> 2, neq=167 [0]PCSetUp_GAMG 2) N=167, n data cols=1, nnz/row (ave)=58, 2 active pes [0]PCGAMGFilterGraph 19.7613% nnz after filtering, with threshold 0.01, 58.2096 nnz ave. [0]maxIndSetAgg removed 0 of 167 vertices. (0 local) 8 selected. [0]PCGAMGProlongator_AGG New grid 8 nodes PCGAMGOptprol_AGG smooth P0: max eigen=1.459581e+00 min=1.292445e-03 PC=jacobi [0]createLevel aggregate processors: npe: 2 --> 1, neq=8 [0]PCSetUp_GAMG 3) N=8, n data cols=1, nnz/row (ave)=8, 1 active pes [0]PCGAMGFilterGraph 56.25% nnz after filtering, with threshold 0.01, 8 nnz ave. [0]maxIndSetAgg removed 0 of 8 vertices. (0 local) 2 selected. [0]PCGAMGProlongator_AGG New grid 2 nodes PCGAMGOptprol_AGG smooth P0: max eigen=2.426409e+00 min=3.017187e-14 PC=jacobi [0]PCSetUp_GAMG 4) N=2, n data cols=1, nnz/row (ave)=2, 1 active pes [0]PCSetUp_GAMG 5 levels, grid complexity = 1.09623 Residual norms for pres_ solve. 0 KSP preconditioned resid norm 3.214004976835e+04 true resid norm 1.537048121012e+01 ||r(i)||/||b|| 1.000000000000e+00 2 KSP preconditioned resid norm 9.962575667075e+03 true resid norm 1.666562709330e+01 ||r(i)||/||b|| 1.084261895609e+00 4 KSP preconditioned resid norm 9.964216763945e+03 true resid norm 1.668511403642e+01 ||r(i)||/||b|| 1.085529711681e+00 6 KSP preconditioned resid norm 1.009624086413e+04 true resid norm 1.899567590778e+01 ||r(i)||/||b|| 1.235854339764e+00 8 KSP preconditioned resid norm 1.119961784740e+04 true resid norm 4.344299871311e+01 ||r(i)||/||b|| 2.826391582620e+00 10 KSP preconditioned resid norm 3.270474238322e+04 true resid norm 5.485695179461e+02 ||r(i)||/||b|| 3.568980765449e+01 12 KSP preconditioned resid norm 6.862047100670e+04 true resid norm 1.392424526518e+03 ||r(i)||/||b|| 9.059082194521e+01 14 KSP preconditioned resid norm 8.020735170110e+04 true resid norm 1.708524744698e+03 ||r(i)||/||b|| 1.111562300062e+02 16 KSP preconditioned resid norm 7.957648213223e+04 true resid norm 1.697241325110e+03 ||r(i)||/||b|| 1.104221333027e+02 18 KSP preconditioned resid norm 7.987861582440e+04 true resid norm 1.720588721880e+03 ||r(i)||/||b|| 1.119411096087e+02 20 KSP preconditioned resid norm 7.781283925015e+04 true resid norm 1.570743019621e+03 ||r(i)||/||b|| 1.021921824144e+02 22 KSP preconditioned resid norm 7.613701956079e+04 true resid norm 1.437142018083e+03 ||r(i)||/||b|| 9.350013174194e+01 24 KSP preconditioned resid norm 7.441069686260e+04 true resid norm 1.291829388291e+03 ||r(i)||/||b|| 8.404612520790e+01 26 KSP preconditioned resid norm 7.381709754141e+04 true resid norm 1.239993290391e+03 ||r(i)||/||b|| 8.067368050748e+01 28 KSP preconditioned resid norm 4.660758247799e+05 true resid norm 1.986383272864e+04 ||r(i)||/||b|| 1.292336424416e+03 30 KSP preconditioned resid norm 3.843023238140e+05 true resid norm 1.626650509205e+04 ||r(i)||/||b|| 1.058295109287e+03 32 KSP preconditioned resid norm 3.807302107274e+05 true resid norm 1.621607637493e+04 ||r(i)||/||b|| 1.055014228459e+03 34 KSP preconditioned resid norm 1.576847461172e+05 true resid norm 3.774334039228e+03 ||r(i)||/||b|| 2.455573112925e+02 36 KSP preconditioned resid norm 1.485636406237e+05 true resid norm 3.409895452504e+03 ||r(i)||/||b|| 2.218470200047e+02 38 KSP preconditioned resid norm 1.453089145230e+05 true resid norm 3.119776988055e+03 ||r(i)||/||b|| 2.029719789125e+02 40 KSP preconditioned resid norm 1.494647504254e+05 true resid norm 2.103792395208e+03 ||r(i)||/||b|| 1.368722531487e+02 42 KSP preconditioned resid norm 1.492528384367e+05 true resid norm 2.105571540467e+03 ||r(i)||/||b|| 1.369880039332e+02 44 KSP preconditioned resid norm 1.495172887683e+05 true resid norm 2.098100475867e+03 ||r(i)||/||b|| 1.365019381752e+02 46 KSP preconditioned resid norm 1.486262786592e+05 true resid norm 2.164181004195e+03 ||r(i)||/||b|| 1.408011222687e+02 48 KSP preconditioned resid norm 1.660465856506e+05 true resid norm 4.172426666954e+03 ||r(i)||/||b|| 2.714571268079e+02 50 KSP preconditioned resid norm 1.482759191221e+05 true resid norm 2.856097129241e+03 ||r(i)||/||b|| 1.858170274696e+02 52 KSP preconditioned resid norm 1.685729081672e+05 true resid norm 5.947178479153e+03 ||r(i)||/||b|| 3.869220747128e+02 54 KSP preconditioned resid norm 1.569362853302e+05 true resid norm 5.573721373030e+03 ||r(i)||/||b|| 3.626250406110e+02 56 KSP preconditioned resid norm 1.572502232797e+05 true resid norm 5.614318099048e+03 ||r(i)||/||b|| 3.652662543416e+02 58 KSP preconditioned resid norm 1.563201382830e+05 true resid norm 5.430932820022e+03 ||r(i)||/||b|| 3.533352499365e+02 60 KSP preconditioned resid norm 1.575394042371e+05 true resid norm 5.517707804827e+03 ||r(i)||/||b|| 3.589808106460e+02 62 KSP preconditioned resid norm 1.574611644503e+05 true resid norm 5.514851203197e+03 ||r(i)||/||b|| 3.587949607958e+02 64 KSP preconditioned resid norm 1.584082961150e+05 true resid norm 5.573531260888e+03 ||r(i)||/||b|| 3.626126719584e+02 66 KSP preconditioned resid norm 1.634951153589e+05 true resid norm 5.910135540989e+03 ||r(i)||/||b|| 3.845120696090e+02 68 KSP preconditioned resid norm 1.647079886374e+05 true resid norm 6.000249380861e+03 ||r(i)||/||b|| 3.903748554672e+02 70 KSP preconditioned resid norm 1.650191144351e+05 true resid norm 6.022517993959e+03 ||r(i)||/||b|| 3.918236463536e+02 72 KSP preconditioned resid norm 1.542157148610e+05 true resid norm 5.403131962522e+03 ||r(i)||/||b|| 3.515265324917e+02 74 KSP preconditioned resid norm 1.554195380312e+05 true resid norm 5.450251819441e+03 ||r(i)||/||b|| 3.545921396302e+02 76 KSP preconditioned resid norm 1.532469232837e+05 true resid norm 5.409499245974e+03 ||r(i)||/||b|| 3.519407865001e+02 78 KSP preconditioned resid norm 1.222695504853e+05 true resid norm 8.087451810483e+03 ||r(i)||/||b|| 5.261677692406e+02 80 KSP preconditioned resid norm 1.144385291371e+05 true resid norm 8.086187300487e+03 ||r(i)||/||b|| 5.260855005089e+02 82 KSP preconditioned resid norm 1.139628084163e+05 true resid norm 8.074654763408e+03 ||r(i)||/||b|| 5.253351962782e+02 84 KSP preconditioned resid norm 9.849803475030e+04 true resid norm 8.340298610024e+03 ||r(i)||/||b|| 5.426179243193e+02 86 KSP preconditioned resid norm 9.841631558189e+04 true resid norm 8.334019324969e+03 ||r(i)||/||b|| 5.422093954666e+02 88 KSP preconditioned resid norm 9.602058427463e+04 true resid norm 8.471718963816e+03 ||r(i)||/||b|| 5.511681025470e+02 90 KSP preconditioned resid norm 9.627762519493e+04 true resid norm 8.455558776172e+03 ||r(i)||/||b|| 5.501167244267e+02 92 KSP preconditioned resid norm 9.628212912916e+04 true resid norm 8.455709739147e+03 ||r(i)||/||b|| 5.501265460433e+02 94 KSP preconditioned resid norm 9.944415339754e+04 true resid norm 8.303497811687e+03 ||r(i)||/||b|| 5.402236727774e+02 96 KSP preconditioned resid norm 1.360957681260e+05 true resid norm 9.342234268251e+03 ||r(i)||/||b|| 6.078036296028e+02 98 KSP preconditioned resid norm 1.028254804925e+06 true resid norm 1.639833993379e+05 ||r(i)||/||b|| 1.066872254006e+04 100 KSP preconditioned resid norm 2.878267699013e+06 true resid norm 5.284924897012e+05 ||r(i)||/||b|| 3.438360077844e+04 102 KSP preconditioned resid norm 3.284723758217e+06 true resid norm 6.019019818184e+05 ||r(i)||/||b|| 3.915960558360e+04 104 KSP preconditioned resid norm 3.490898600321e+06 true resid norm 6.386257805102e+05 ||r(i)||/||b|| 4.154884754615e+04 106 KSP preconditioned resid norm 4.292371780598e+06 true resid norm 7.825387697929e+05 ||r(i)||/||b|| 5.091179378807e+04 108 KSP preconditioned resid norm 4.272469798938e+06 true resid norm 7.783966012792e+05 ||r(i)||/||b|| 5.064230524980e+04 110 KSP preconditioned resid norm 3.932496986313e+06 true resid norm 7.284977182706e+05 ||r(i)||/||b|| 4.739589530814e+04 112 KSP preconditioned resid norm 3.938646883327e+06 true resid norm 7.296330278220e+05 ||r(i)||/||b|| 4.746975828848e+04 114 KSP preconditioned resid norm 3.108284574985e+06 true resid norm 6.043424330292e+05 ||r(i)||/||b|| 3.931838078246e+04 116 KSP preconditioned resid norm 3.382223114783e+06 true resid norm 3.235035948244e+05 ||r(i)||/||b|| 2.104707005604e+04 118 KSP preconditioned resid norm 3.034407011811e+06 true resid norm 3.294035179204e+05 ||r(i)||/||b|| 2.143091770630e+04 Linear solve did not converge due to DIVERGED_ITS iterations 118 KSP Object:(pres_) 4 MPI processes type: bcgsl BCGSL: Ell = 2 BCGSL: Delta = 0 maximum iterations=120 tolerances: relative=1e-08, absolute=1e-50, divergence=10000 left preconditioning has attached null space using nonzero initial guess using PRECONDITIONED norm type for convergence test PC Object:(pres_) 4 MPI processes type: gamg MG: type is MULTIPLICATIVE, levels=5 cycles=v Cycles per PCApply=1 Using Galerkin computed coarse grid matrices Coarse grid solver -- level ------------------------------- KSP Object: (pres_mg_coarse_) 4 MPI processes type: preonly maximum iterations=1, initial guess is zero tolerances: relative=1e-05, absolute=1e-50, divergence=10000 left preconditioning using NONE norm type for convergence test PC Object: (pres_mg_coarse_) 4 MPI processes type: sor SOR: type = local_symmetric, iterations = 1, local iterations = 1, omega = 1 linear system matrix = precond matrix: Matrix Object: 4 MPI processes type: mpiaij rows=2, cols=2 total: nonzeros=4, allocated nonzeros=4 total number of mallocs used during MatSetValues calls =0 using I-node (on process 0) routines: found 1 nodes, limit used is 5 Down solver (pre-smoother) on level 1 ------------------------------- KSP Object: (pres_mg_levels_1_) 4 MPI processes type: richardson Richardson: damping factor=1 maximum iterations=1 tolerances: relative=1e-05, absolute=1e-50, divergence=10000 left preconditioning using nonzero initial guess using NONE norm type for convergence test PC Object: (pres_mg_levels_1_) 4 MPI processes type: sor SOR: type = local_symmetric, iterations = 1, local iterations = 1, omega = 1 linear system matrix = precond matrix: Matrix Object: 4 MPI processes type: mpiaij rows=8, cols=8 total: nonzeros=64, allocated nonzeros=64 total number of mallocs used during MatSetValues calls =0 using I-node (on process 0) routines: found 2 nodes, limit used is 5 Up solver (post-smoother) same as down solver (pre-smoother) Down solver (pre-smoother) on level 2 ------------------------------- KSP Object: (pres_mg_levels_2_) 4 MPI processes type: richardson Richardson: damping factor=1 maximum iterations=1 tolerances: relative=1e-05, absolute=1e-50, divergence=10000 left preconditioning using nonzero initial guess using NONE norm type for convergence test PC Object: (pres_mg_levels_2_) 4 MPI processes type: sor SOR: type = local_symmetric, iterations = 1, local iterations = 1, omega = 1 linear system matrix = precond matrix: Matrix Object: 4 MPI processes type: mpiaij rows=167, cols=167 total: nonzeros=9721, allocated nonzeros=9721 total number of mallocs used during MatSetValues calls =0 not using I-node (on process 0) routines Up solver (post-smoother) same as down solver (pre-smoother) Down solver (pre-smoother) on level 3 ------------------------------- KSP Object: (pres_mg_levels_3_) 4 MPI processes type: richardson Richardson: damping factor=1 maximum iterations=1 tolerances: relative=1e-05, absolute=1e-50, divergence=10000 left preconditioning using nonzero initial guess using NONE norm type for convergence test PC Object: (pres_mg_levels_3_) 4 MPI processes type: sor SOR: type = local_symmetric, iterations = 1, local iterations = 1, omega = 1 linear system matrix = precond matrix: Matrix Object: 4 MPI processes type: mpiaij rows=6937, cols=6937 total: nonzeros=440237, allocated nonzeros=440237 total number of mallocs used during MatSetValues calls =0 not using I-node (on process 0) routines Up solver (post-smoother) same as down solver (pre-smoother) Down solver (pre-smoother) on level 4 ------------------------------- KSP Object: (pres_mg_levels_4_) 4 MPI processes type: richardson Richardson: damping factor=1 maximum iterations=1 tolerances: relative=1e-05, absolute=1e-50, divergence=10000 left preconditioning has attached null space using nonzero initial guess using NONE norm type for convergence test PC Object: (pres_mg_levels_4_) 4 MPI processes type: sor SOR: type = local_symmetric, iterations = 1, local iterations = 1, omega = 1 linear system matrix = precond matrix: Matrix Object: 4 MPI processes type: mpiaij rows=178085, cols=178085 total: nonzeros=4676387, allocated nonzeros=8374105 total number of mallocs used during MatSetValues calls =0 not using I-node (on process 0) routines Up solver (post-smoother) same as down solver (pre-smoother) linear system matrix = precond matrix: Matrix Object: 4 MPI processes type: mpiaij rows=178085, cols=178085 total: nonzeros=4676387, allocated nonzeros=8374105 total number of mallocs used during MatSetValues calls =0 not using I-node (on process 0) routines WARNING! There are options you set that were not used! WARNING! could be spelling mistake, etc! Option left: name: -pres_options_left no value RUN2: Options: -pres_ksp_type bcgsl -pres_pc_type gamg -pres_pc_gamg_sym_graph -pres_pc_gamg_coarse_eq_limit 8 -pres_pc_gamg_agg_nsmooths 1 -pres_pc_gamg_threshold 0.01 -pres_mg_levels_ksp_type richardson -pres_mg_levels_pc_type sor -pres_mg_coarse_ksp_type richardson -pres_mg_coarse_pc_type sor -pres_mg_coarse_pc_sor_its 1 -pres_ksp_monitor_true_residual -pres_pc_gamg_verbose 2 -pres_ksp_view -pres_options_left [0]PCSetFromOptions_GAMG threshold set 1.000000e-02 [0]PCSetUp_GAMG level 0 N=178085, n data rows=1, n data cols=1, nnz/row (ave)=26, np=4 [0]PCGAMGFilterGraph 64.0278% nnz after filtering, with threshold 0.01, 26.2593 nnz ave. [0]maxIndSetAgg removed 0 of 178085 vertices. (0 local) 6937 selected. [0]PCGAMGProlongator_AGG New grid 6937 nodes PCGAMGOptprol_AGG smooth P0: max eigen=1.927344e+00 min=4.441888e-02 PC=jacobi [0]PCSetUp_GAMG 1) N=6937, n data cols=1, nnz/row (ave)=63, 4 active pes [0]PCGAMGFilterGraph 32.3853% nnz after filtering, with threshold 0.01, 63.4622 nnz ave. [0]maxIndSetAgg removed 0 of 6937 vertices. (0 local) 167 selected. [0]PCGAMGProlongator_AGG New grid 167 nodes PCGAMGOptprol_AGG smooth P0: max eigen=4.364217e+00 min=5.712156e-03 PC=jacobi [0]createLevel aggregate processors: npe: 4 --> 2, neq=167 [0]PCSetUp_GAMG 2) N=167, n data cols=1, nnz/row (ave)=58, 2 active pes [0]PCGAMGFilterGraph 19.7613% nnz after filtering, with threshold 0.01, 58.2096 nnz ave. [0]maxIndSetAgg removed 0 of 167 vertices. (0 local) 8 selected. [0]PCGAMGProlongator_AGG New grid 8 nodes PCGAMGOptprol_AGG smooth P0: max eigen=1.459581e+00 min=1.292445e-03 PC=jacobi [0]createLevel aggregate processors: npe: 2 --> 1, neq=8 [0]PCSetUp_GAMG 3) N=8, n data cols=1, nnz/row (ave)=8, 1 active pes [0]PCSetUp_GAMG 4 levels, grid complexity = 1.09623 Residual norms for pres_ solve. 0 KSP preconditioned resid norm 1.210558693457e+04 true resid norm 1.537048121012e+01 ||r(i)||/||b|| 1.000000000000e+00 2 KSP preconditioned resid norm 4.471234066863e+03 true resid norm 5.782528108610e+01 ||r(i)||/||b|| 3.762099591783e+00 4 KSP preconditioned resid norm 5.705586099552e+02 true resid norm 1.766618406384e+01 ||r(i)||/||b|| 1.149357903786e+00 6 KSP preconditioned resid norm 2.630493890369e+02 true resid norm 4.130300513941e+00 ||r(i)||/||b|| 2.687164089060e-01 8 KSP preconditioned resid norm 1.622096002911e+01 true resid norm 3.985823191611e-01 ||r(i)||/||b|| 2.593167472849e-02 10 KSP preconditioned resid norm 1.166276779499e+01 true resid norm 1.933128706628e-01 ||r(i)||/||b|| 1.257689125149e-02 12 KSP preconditioned resid norm 8.600869344082e-01 true resid norm 1.497599703252e-02 ||r(i)||/||b|| 9.743349494267e-04 14 KSP preconditioned resid norm 1.478956802605e-01 true resid norm 1.829141074894e-03 ||r(i)||/||b|| 1.190035009242e-04 16 KSP preconditioned resid norm 2.089299129489e-02 true resid norm 3.275473585379e-04 ||r(i)||/||b|| 2.131015640046e-05 18 KSP preconditioned resid norm 1.222936568425e-03 true resid norm 4.389356922168e-05 ||r(i)||/||b|| 2.855705597088e-06 20 KSP preconditioned resid norm 2.108428382409e-03 true resid norm 2.784330122700e-05 ||r(i)||/||b|| 1.811478824012e-06 22 KSP preconditioned resid norm 1.051218867616e-04 true resid norm 1.044274089421e-05 ||r(i)||/||b|| 6.794023395530e-07 Linear solve converged due to CONVERGED_RTOL iterations 22 KSP Object:(pres_) 4 MPI processes type: bcgsl BCGSL: Ell = 2 BCGSL: Delta = 0 maximum iterations=120 tolerances: relative=1e-08, absolute=1e-50, divergence=10000 left preconditioning has attached null space using nonzero initial guess using PRECONDITIONED norm type for convergence test PC Object:(pres_) 4 MPI processes type: gamg MG: type is MULTIPLICATIVE, levels=4 cycles=v Cycles per PCApply=1 Using Galerkin computed coarse grid matrices Coarse grid solver -- level ------------------------------- KSP Object: (pres_mg_coarse_) 4 MPI processes type: preonly maximum iterations=1, initial guess is zero tolerances: relative=1e-05, absolute=1e-50, divergence=10000 left preconditioning using NONE norm type for convergence test PC Object: (pres_mg_coarse_) 4 MPI processes type: sor SOR: type = local_symmetric, iterations = 1, local iterations = 1, omega = 1 linear system matrix = precond matrix: Matrix Object: 4 MPI processes type: mpiaij rows=8, cols=8 total: nonzeros=64, allocated nonzeros=64 total number of mallocs used during MatSetValues calls =0 using I-node (on process 0) routines: found 2 nodes, limit used is 5 Down solver (pre-smoother) on level 1 ------------------------------- KSP Object: (pres_mg_levels_1_) 4 MPI processes type: richardson Richardson: damping factor=1 maximum iterations=1 tolerances: relative=1e-05, absolute=1e-50, divergence=10000 left preconditioning using nonzero initial guess using NONE norm type for convergence test PC Object: (pres_mg_levels_1_) 4 MPI processes type: sor SOR: type = local_symmetric, iterations = 1, local iterations = 1, omega = 1 linear system matrix = precond matrix: Matrix Object: 4 MPI processes type: mpiaij rows=167, cols=167 total: nonzeros=9721, allocated nonzeros=9721 total number of mallocs used during MatSetValues calls =0 not using I-node (on process 0) routines Up solver (post-smoother) same as down solver (pre-smoother) Down solver (pre-smoother) on level 2 ------------------------------- KSP Object: (pres_mg_levels_2_) 4 MPI processes type: richardson Richardson: damping factor=1 maximum iterations=1 tolerances: relative=1e-05, absolute=1e-50, divergence=10000 left preconditioning using nonzero initial guess using NONE norm type for convergence test PC Object: (pres_mg_levels_2_) 4 MPI processes type: sor SOR: type = local_symmetric, iterations = 1, local iterations = 1, omega = 1 linear system matrix = precond matrix: Matrix Object: 4 MPI processes type: mpiaij rows=6937, cols=6937 total: nonzeros=440237, allocated nonzeros=440237 total number of mallocs used during MatSetValues calls =0 not using I-node (on process 0) routines Up solver (post-smoother) same as down solver (pre-smoother) Down solver (pre-smoother) on level 3 ------------------------------- KSP Object: (pres_mg_levels_3_) 4 MPI processes type: richardson Richardson: damping factor=1 maximum iterations=1 tolerances: relative=1e-05, absolute=1e-50, divergence=10000 left preconditioning has attached null space using nonzero initial guess using NONE norm type for convergence test PC Object: (pres_mg_levels_3_) 4 MPI processes type: sor SOR: type = local_symmetric, iterations = 1, local iterations = 1, omega = 1 linear system matrix = precond matrix: Matrix Object: 4 MPI processes type: mpiaij rows=178085, cols=178085 total: nonzeros=4676387, allocated nonzeros=8374105 total number of mallocs used during MatSetValues calls =0 not using I-node (on process 0) routines Up solver (post-smoother) same as down solver (pre-smoother) linear system matrix = precond matrix: Matrix Object: 4 MPI processes type: mpiaij rows=178085, cols=178085 total: nonzeros=4676387, allocated nonzeros=8374105 total number of mallocs used during MatSetValues calls =0 not using I-node (on process 0) routines WARNING! There are options you set that were not used! WARNING! could be spelling mistake, etc! Option left: name:-pres_options_left no value
