[petsc-users] CPR-AMG: SNES with two cores worse than with one
Barry Smith
bsmith at mcs.anl.gov
Thu Jul 6 15:24:03 CDT 2017
So on one process the outer linear solver takes a single iteration this is because the block Jacobi with LU and one block is a direct solver.
> 11 KSP preconditioned resid norm 1.131868956745e+00 true resid norm 1.526261825526e-05 ||r(i)||/||b|| 1.485509868409e-05
> [0] KSPConvergedDefault(): Linear solver has converged. Residual norm 2.148515820410e-14 is less than relative tolerance 1.000000000000e-07 times initial right hand side norm 1.581814306485e-02 at iteration 1
> 1 KSP unpreconditioned resid norm 2.148515820410e-14 true resid norm 2.148698024622e-14 ||r(i)||/||b|| 1.358375642332e-12
On two processes the outer linear solver takes a few iterations to solver, this is to be expected.
But what you sent doesn't give any indication about SNES not converging. Please turn off all inner linear solver monitoring and just run with -ksp_monitor_true_residual -snes_monitor -snes_lineseach_monitor -snes_converged_reason
Barry
> On Jul 6, 2017, at 2:03 PM, Robert Annewandter <robert.annewandter at opengosim.com> wrote:
>
> Hi all,
>
> I like to understand why the SNES of my CPR-AMG Two-Stage Preconditioner (with KSPFGMRES + multipl. PCComposite (PCGalerkin with KSPGMRES + BoomerAMG, PCBJacobi + PCLU init) on a 24,000 x 24,000 matrix) struggles to converge when using two cores instead of one. Because of the adaptive time stepping of the Newton, this leads to severe cuts in time step.
>
> This is how I run it with two cores
>
> mpirun \
> -n 2 pflotran \
> -pflotranin het.pflinput \
> -ksp_monitor_true_residual \
> -flow_snes_view \
> -flow_snes_converged_reason \
> -flow_sub_1_pc_type bjacobi \
> -flow_sub_1_sub_pc_type lu \
> -flow_sub_1_sub_pc_factor_pivot_in_blocks true\
> -flow_sub_1_sub_pc_factor_nonzeros_along_diagonal \
> -options_left \
> -log_summary \
> -info
>
>
> With one core I get (after grepping the crap away from -info):
>
> Step 32 Time= 1.80000E+01
>
> [...]
>
> 0 2r: 1.58E-02 2x: 0.00E+00 2u: 0.00E+00 ir: 7.18E-03 iu: 0.00E+00 rsn: 0
> [0] SNESComputeJacobian(): Rebuilding preconditioner
> Residual norms for flow_ solve.
> 0 KSP unpreconditioned resid norm 1.581814306485e-02 true resid norm 1.581814306485e-02 ||r(i)||/||b|| 1.000000000000e+00
> Residual norms for flow_sub_0_galerkin_ solve.
> 0 KSP preconditioned resid norm 5.697603110484e+07 true resid norm 5.175721849125e+03 ||r(i)||/||b|| 5.037527476892e+03
> 1 KSP preconditioned resid norm 5.041509073319e+06 true resid norm 3.251596928176e+02 ||r(i)||/||b|| 3.164777657484e+02
> 2 KSP preconditioned resid norm 1.043761838360e+06 true resid norm 8.957519558348e+01 ||r(i)||/||b|| 8.718349288342e+01
> 3 KSP preconditioned resid norm 1.129189815646e+05 true resid norm 2.722436912053e+00 ||r(i)||/||b|| 2.649746479496e+00
> 4 KSP preconditioned resid norm 8.829637298082e+04 true resid norm 8.026373593492e+00 ||r(i)||/||b|| 7.812065388300e+00
> 5 KSP preconditioned resid norm 6.506021637694e+04 true resid norm 3.479889319880e+00 ||r(i)||/||b|| 3.386974527698e+00
> 6 KSP preconditioned resid norm 6.392263200180e+04 true resid norm 3.819202631980e+00 ||r(i)||/||b|| 3.717228003987e+00
> 7 KSP preconditioned resid norm 2.464946645480e+04 true resid norm 7.329964753388e-01 ||r(i)||/||b|| 7.134251013911e-01
> 8 KSP preconditioned resid norm 2.603879153772e+03 true resid norm 2.035525412004e-02 ||r(i)||/||b|| 1.981175861414e-02
> 9 KSP preconditioned resid norm 1.774410462754e+02 true resid norm 3.001214973121e-03 ||r(i)||/||b|| 2.921081026352e-03
> 10 KSP preconditioned resid norm 1.664227038378e+01 true resid norm 3.413136309181e-04 ||r(i)||/||b|| 3.322003855903e-04
> [0] KSPConvergedDefault(): Linear solver has converged. Residual norm 1.131868956745e+00 is less than relative tolerance 1.000000000000e-07 times initial right hand side norm 2.067297386780e+07 at iteration 11
> 11 KSP preconditioned resid norm 1.131868956745e+00 true resid norm 1.526261825526e-05 ||r(i)||/||b|| 1.485509868409e-05
> [0] KSPConvergedDefault(): Linear solver has converged. Residual norm 2.148515820410e-14 is less than relative tolerance 1.000000000000e-07 times initial right hand side norm 1.581814306485e-02 at iteration 1
> 1 KSP unpreconditioned resid norm 2.148515820410e-14 true resid norm 2.148698024622e-14 ||r(i)||/||b|| 1.358375642332e-12
> [0] SNESSolve_NEWTONLS(): iter=0, linear solve iterations=1
> [0] SNESNEWTONLSCheckResidual_Private(): ||J^T(F-Ax)||/||F-AX|| 3.590873180642e-01 near zero implies inconsistent rhs
> [0] SNESSolve_NEWTONLS(): fnorm=1.5818143064846742e-02, gnorm=1.0695649833687331e-02, ynorm=4.6826522561266171e+02, lssucceed=0
> [0] SNESConvergedDefault(): Converged due to small update length: 4.682652256127e+02 < 1.000000000000e-05 * 3.702480426117e+09
> 1 2r: 1.07E-02 2x: 3.70E+09 2u: 4.68E+02 ir: 5.05E-03 iu: 4.77E+01 rsn: stol
> Nonlinear flow_ solve converged due to CONVERGED_SNORM_RELATIVE iterations 1
>
>
>
> But with two cores I get:
>
>
> Step 32 Time= 1.80000E+01
>
> [...]
>
> 0 2r: 6.16E-03 2x: 0.00E+00 2u: 0.00E+00 ir: 3.63E-03 iu: 0.00E+00 rsn: 0
> [0] SNESComputeJacobian(): Rebuilding preconditioner
>
> Residual norms for flow_ solve.
> 0 KSP unpreconditioned resid norm 6.162760088924e-03 true resid norm 6.162760088924e-03 ||r(i)||/||b|| 1.000000000000e+00
> Residual norms for flow_sub_0_galerkin_ solve.
> 0 KSP preconditioned resid norm 8.994949630499e+08 true resid norm 7.982144380936e-01 ||r(i)||/||b|| 1.000000000000e+00
> 1 KSP preconditioned resid norm 8.950556502615e+08 true resid norm 1.550138696155e+00 ||r(i)||/||b|| 1.942007839218e+00
> 2 KSP preconditioned resid norm 1.044849684205e+08 true resid norm 2.166193480531e+00 ||r(i)||/||b|| 2.713798920631e+00
> 3 KSP preconditioned resid norm 8.209708619718e+06 true resid norm 3.076045005154e-01 ||r(i)||/||b|| 3.853657436340e-01
> 4 KSP preconditioned resid norm 3.027461352422e+05 true resid norm 1.207731865714e-02 ||r(i)||/||b|| 1.513041869549e-02
> 5 KSP preconditioned resid norm 1.595302164817e+04 true resid norm 4.123713694368e-04 ||r(i)||/||b|| 5.166172769585e-04
> 6 KSP preconditioned resid norm 1.898935810797e+03 true resid norm 8.275885058330e-05 ||r(i)||/||b|| 1.036799719897e-04
> 7 KSP preconditioned resid norm 1.429881682558e+02 true resid norm 4.751240525466e-06 ||r(i)||/||b|| 5.952335987324e-06
> [0] KSPConvergedDefault(): Linear solver has converged. Residual norm 8.404003313455e+00 is less than relative tolerance 1.000000000000e-07 times initial right hand side norm 8.994949630499e+08 at iteration 8
> 8 KSP preconditioned resid norm 8.404003313455e+00 true resid norm 3.841921844578e-07 ||r(i)||/||b|| 4.813145016211e-07
> 1 KSP unpreconditioned resid norm 6.162162548202e-03 true resid norm 6.162162548202e-03 ||r(i)||/||b|| 9.999030400804e-01
> Residual norms for flow_sub_0_galerkin_ solve.
> 0 KSP preconditioned resid norm 4.360556381209e+07 true resid norm 1.000000245433e+00 ||r(i)||/||b|| 1.000000000000e+00
> 1 KSP preconditioned resid norm 5.385519331932e+06 true resid norm 8.785183939860e-02 ||r(i)||/||b|| 8.785181783689e-02
> 2 KSP preconditioned resid norm 4.728931283459e+05 true resid norm 2.008708805316e-02 ||r(i)||/||b|| 2.008708312313e-02
> 3 KSP preconditioned resid norm 2.734215698319e+04 true resid norm 6.418720397673e-03 ||r(i)||/||b|| 6.418718822309e-03
> 4 KSP preconditioned resid norm 1.002270029334e+04 true resid norm 4.040289515991e-03 ||r(i)||/||b|| 4.040288524372e-03
> 5 KSP preconditioned resid norm 1.321280190971e+03 true resid norm 1.023292238313e-04 ||r(i)||/||b|| 1.023291987163e-04
> 6 KSP preconditioned resid norm 6.594292964815e+01 true resid norm 1.877106733170e-06 ||r(i)||/||b|| 1.877106272467e-06
> 7 KSP preconditioned resid norm 7.816325147216e+00 true resid norm 2.552611664980e-07 ||r(i)||/||b|| 2.552611038486e-07
> [0] KSPConvergedDefault(): Linear solver has converged. Residual norm 6.391568446109e-01 is less than relative tolerance 1.000000000000e-07 times initial right hand side norm 4.360556381209e+07 at iteration 8
> 8 KSP preconditioned resid norm 6.391568446109e-01 true resid norm 1.680724939670e-08 ||r(i)||/||b|| 1.680724527166e-08
> 2 KSP unpreconditioned resid norm 4.328902922753e-07 true resid norm 4.328902922752e-07 ||r(i)||/||b|| 7.024292460341e-05
> Residual norms for flow_sub_0_galerkin_ solve.
> 0 KSP preconditioned resid norm 8.794597825780e+08 true resid norm 1.000000094566e+00 ||r(i)||/||b|| 1.000000000000e+00
> 1 KSP preconditioned resid norm 8.609906572102e+08 true resid norm 2.965044981249e+00 ||r(i)||/||b|| 2.965044700856e+00
> 2 KSP preconditioned resid norm 9.318108989314e+07 true resid norm 1.881262939380e+00 ||r(i)||/||b|| 1.881262761477e+00
> 3 KSP preconditioned resid norm 6.908723262483e+06 true resid norm 2.639592490398e-01 ||r(i)||/||b|| 2.639592240782e-01
> 4 KSP preconditioned resid norm 2.651677791227e+05 true resid norm 9.736480169584e-03 ||r(i)||/||b|| 9.736479248845e-03
> 5 KSP preconditioned resid norm 1.192178471172e+04 true resid norm 3.082839752692e-04 ||r(i)||/||b|| 3.082839461160e-04
> 6 KSP preconditioned resid norm 1.492201446262e+03 true resid norm 4.633866284506e-05 ||r(i)||/||b|| 4.633865846301e-05
> 7 KSP preconditioned resid norm 1.160670017241e+02 true resid norm 2.821157348522e-06 ||r(i)||/||b|| 2.821157081737e-06
> [0] KSPConvergedDefault(): Linear solver has converged. Residual norm 6.447568262216e+00 is less than relative tolerance 1.000000000000e-07 times initial right hand side norm 8.794597825780e+08 at iteration 8
> 8 KSP preconditioned resid norm 6.447568262216e+00 true resid norm 1.516068561348e-07 ||r(i)||/||b|| 1.516068417980e-07
> [0] KSPConvergedDefault(): Linear solver has converged. Residual norm 6.135731709822e-15 is less than relative tolerance 1.000000000000e-07 times initial right hand side norm 6.162760088924e-03 at iteration 3
> 3 KSP unpreconditioned resid norm 6.135731709822e-15 true resid norm 1.142020328809e-14 ||r(i)||/||b|| 1.853098793933e-12
>
> [0] SNESSolve_NEWTONLS(): iter=0, linear solve iterations=3
> [0] SNESNEWTONLSCheckResidual_Private(): ||J^T(F-Ax)||/||F-AX|| 1.998388224666e-02 near zero implies inconsistent rhs
> [0] SNESSolve_NEWTONLS(): fnorm=6.1627600889243711e-03, gnorm=1.0406503258190572e-02, ynorm=6.2999025681245366e+04, lssucceed=0
> 1 2r: 1.04E-02 2x: 3.70E+09 2u: 6.30E+04 ir: 6.54E-03 iu: 5.00E+04 rsn: 0
> [0] SNESComputeJacobian(): Rebuilding preconditioner
>
> Residual norms for flow_ solve.
> 0 KSP unpreconditioned resid norm 1.040650325819e-02 true resid norm 1.040650325819e-02 ||r(i)||/||b|| 1.000000000000e+00
> Residual norms for flow_sub_0_galerkin_ solve.
> 0 KSP preconditioned resid norm 6.758906811264e+07 true resid norm 9.814998431686e-01 ||r(i)||/||b|| 1.000000000000e+00
> 1 KSP preconditioned resid norm 2.503922806424e+06 true resid norm 2.275130113021e-01 ||r(i)||/||b|| 2.318013730574e-01
> 2 KSP preconditioned resid norm 3.316753614870e+05 true resid norm 3.820733530238e-02 ||r(i)||/||b|| 3.892750016040e-02
> 3 KSP preconditioned resid norm 2.956751700483e+04 true resid norm 2.143772538677e-03 ||r(i)||/||b|| 2.184180215207e-03
> 4 KSP preconditioned resid norm 1.277067042524e+03 true resid norm 9.093614251311e-05 ||r(i)||/||b|| 9.265018547485e-05
> 5 KSP preconditioned resid norm 1.060996002446e+02 true resid norm 1.042893700050e-05 ||r(i)||/||b|| 1.062551061326e-05
> [0] KSPConvergedDefault(): Linear solver has converged. Residual norm 5.058127343285e+00 is less than relative tolerance 1.000000000000e-07 times initial right hand side norm 6.758906811264e+07 at iteration 6
> 6 KSP preconditioned resid norm 5.058127343285e+00 true resid norm 4.054770602120e-07 ||r(i)||/||b|| 4.131198420807e-07
> [0] KSPConvergedDefault(): Linear solver has converged. Residual norm 4.449606189225e-10 is less than relative tolerance 1.000000000000e-07 times initial right hand side norm 1.040650325819e-02 at iteration 1
> 1 KSP unpreconditioned resid norm 4.449606189225e-10 true resid norm 4.449606189353e-10 ||r(i)||/||b|| 4.275793779098e-08
>
> [0] SNESSolve_NEWTONLS(): iter=1, linear solve iterations=1
> [0] SNESNEWTONLSCheckResidual_Private(): ||J^T(F-Ax)||/||F-AX|| 4.300066663571e-02 near zero implies inconsistent rhs
> [0] SNESSolve_NEWTONLS(): fnorm=1.0406503258190572e-02, gnorm=7.3566280848133728e-02, ynorm=7.9500485128639993e+04, lssucceed=0
> 2 2r: 7.36E-02 2x: 3.70E+09 2u: 7.95E+04 ir: 4.62E-02 iu: 5.00E+04 rsn: 0
> [0] SNESComputeJacobian(): Rebuilding preconditioner
>
> Residual norms for flow_ solve.
> 0 KSP unpreconditioned resid norm 7.356628084813e-02 true resid norm 7.356628084813e-02 ||r(i)||/||b|| 1.000000000000e+00
> Residual norms for flow_sub_0_galerkin_ solve.
> 0 KSP preconditioned resid norm 7.253424029194e+06 true resid norm 9.647008645250e-01 ||r(i)||/||b|| 1.000000000000e+00
> 1 KSP preconditioned resid norm 7.126940190688e+06 true resid norm 1.228009197928e+00 ||r(i)||/||b|| 1.272942984800e+00
> 2 KSP preconditioned resid norm 9.391591432635e+05 true resid norm 7.804929162756e-01 ||r(i)||/||b|| 8.090517433711e-01
> 3 KSP preconditioned resid norm 6.538499674761e+04 true resid norm 5.503467432893e-02 ||r(i)||/||b|| 5.704843475602e-02
> 4 KSP preconditioned resid norm 1.593713396575e+04 true resid norm 8.902701363763e-02 ||r(i)||/||b|| 9.228457951208e-02
> 5 KSP preconditioned resid norm 4.837260621464e+02 true resid norm 2.966772992825e-03 ||r(i)||/||b|| 3.075329464213e-03
> 6 KSP preconditioned resid norm 1.681372767335e+02 true resid norm 5.312467443025e-04 ||r(i)||/||b|| 5.506854651406e-04
> 7 KSP preconditioned resid norm 1.271478850717e+01 true resid norm 2.123810020488e-05 ||r(i)||/||b|| 2.201521838103e-05
> 8 KSP preconditioned resid norm 1.262723712696e+00 true resid norm 1.150572715331e-06 ||r(i)||/||b|| 1.192673042641e-06
> [0] KSPConvergedDefault(): Linear solver has converged. Residual norm 9.053072585125e-02 is less than relative tolerance 1.000000000000e-07 times initial right hand side norm 7.253424029194e+06 at iteration 9
> 9 KSP preconditioned resid norm 9.053072585125e-02 true resid norm 9.475050575058e-08 ||r(i)||/||b|| 9.821749853747e-08
> 1 KSP unpreconditioned resid norm 8.171589173162e-03 true resid norm 8.171589173162e-03 ||r(i)||/||b|| 1.110779161180e-01
> Residual norms for flow_sub_0_galerkin_ solve.
> 0 KSP preconditioned resid norm 4.345765068989e+07 true resid norm 9.999992231691e-01 ||r(i)||/||b|| 1.000000000000e+00
> 1 KSP preconditioned resid norm 5.388715093466e+06 true resid norm 8.125387327699e-02 ||r(i)||/||b|| 8.125393639755e-02
> 2 KSP preconditioned resid norm 4.763725726436e+05 true resid norm 2.464285618036e-02 ||r(i)||/||b|| 2.464287532371e-02
> 3 KSP preconditioned resid norm 2.287746683380e+04 true resid norm 7.224823080100e-03 ||r(i)||/||b|| 7.224828692570e-03
> 4 KSP preconditioned resid norm 4.872858764091e+03 true resid norm 3.972261388893e-03 ||r(i)||/||b|| 3.972264474670e-03
> 5 KSP preconditioned resid norm 8.670449895323e+02 true resid norm 2.359005963873e-04 ||r(i)||/||b|| 2.359007796423e-04
> 6 KSP preconditioned resid norm 4.252589693890e+01 true resid norm 1.471904261226e-06 ||r(i)||/||b|| 1.471905404648e-06
> 7 KSP preconditioned resid norm 5.128476471782e+00 true resid norm 1.643725157865e-07 ||r(i)||/||b|| 1.643726434763e-07
> [0] KSPConvergedDefault(): Linear solver has converged. Residual norm 4.311901915856e-01 is less than relative tolerance 1.000000000000e-07 times initial right hand side norm 4.345765068989e+07 at iteration 8
> 8 KSP preconditioned resid norm 4.311901915856e-01 true resid norm 1.166123921637e-08 ||r(i)||/||b|| 1.166124827519e-08
> [0] KSPConvergedDefault(): Linear solver has converged. Residual norm 2.373662391739e-09 is less than relative tolerance 1.000000000000e-07 times initial right hand side norm 7.356628084813e-02 at iteration 2
> 2 KSP unpreconditioned resid norm 2.373662391739e-09 true resid norm 2.373662391658e-09 ||r(i)||/||b|| 3.226562990941e-08
>
> [0] SNESSolve_NEWTONLS(): iter=2, linear solve iterations=2
> [0] SNESNEWTONLSCheckResidual_Private(): ||J^T(F-Ax)||/||F-AX|| 4.343326231305e-02 near zero implies inconsistent rhs
> [0] SNESSolve_NEWTONLS(): fnorm=7.3566280848133728e-02, gnorm=7.2259942496422647e-02, ynorm=6.3156901950486099e+04, lssucceed=0
> 3 2r: 7.23E-02 2x: 3.70E+09 2u: 6.32E+04 ir: 4.52E-02 iu: 5.00E+04 rsn: 0
> [0] SNESComputeJacobian(): Rebuilding preconditioner
>
> Residual norms for flow_ solve.
> 0 KSP unpreconditioned resid norm 7.225994249642e-02 true resid norm 7.225994249642e-02 ||r(i)||/||b|| 1.000000000000e+00
> Residual norms for flow_sub_0_galerkin_ solve.
> 0 KSP preconditioned resid norm 7.705582590638e+05 true resid norm 9.649751442741e-01 ||r(i)||/||b|| 1.000000000000e+00
> 1 KSP preconditioned resid norm 2.444424220392e+04 true resid norm 8.243110200738e-03 ||r(i)||/||b|| 8.542303135630e-03
> 2 KSP preconditioned resid norm 2.080899648412e+03 true resid norm 7.642343147053e-04 ||r(i)||/||b|| 7.919730567570e-04
> 3 KSP preconditioned resid norm 9.911171129874e+02 true resid norm 5.904182179180e-05 ||r(i)||/||b|| 6.118481096859e-05
> 4 KSP preconditioned resid norm 5.258230282482e+02 true resid norm 2.043366677644e-04 ||r(i)||/||b|| 2.117532964210e-04
> 5 KSP preconditioned resid norm 5.522830460456e+01 true resid norm 1.710780366056e-05 ||r(i)||/||b|| 1.772875059225e-05
> 6 KSP preconditioned resid norm 5.922280741715e+00 true resid norm 1.543198740828e-06 ||r(i)||/||b|| 1.599210870855e-06
> 7 KSP preconditioned resid norm 3.339500859115e-01 true resid norm 1.221335666427e-07 ||r(i)||/||b|| 1.265665414984e-07
> [0] KSPConvergedDefault(): Linear solver has converged. Residual norm 3.329208597672e-02 is less than relative tolerance 1.000000000000e-07 times initial right hand side norm 7.705582590638e+05 at iteration 8
> 8 KSP preconditioned resid norm 3.329208597672e-02 true resid norm 9.758240835324e-09 ||r(i)||/||b|| 1.011242713683e-08
> [0] KSPConvergedDefault(): Linear solver has converged. Residual norm 2.697128456432e-11 is less than relative tolerance 1.000000000000e-07 times initial right hand side norm 7.225994249642e-02 at iteration 1
> 1 KSP unpreconditioned resid norm 2.697128456432e-11 true resid norm 2.697128457142e-11 ||r(i)||/||b|| 3.732536124389e-10
>
> [0] SNESSolve_NEWTONLS(): iter=3, linear solve iterations=1
> [0] SNESNEWTONLSCheckResidual_Private(): ||J^T(F-Ax)||/||F-AX|| 4.329227684222e-02 near zero implies inconsistent rhs
> [0] SNESSolve_NEWTONLS(): fnorm=7.2259942496422647e-02, gnorm=5.4435602192925014e-01, ynorm=2.7049750229137400e+04, lssucceed=0
> [0] SNESConvergedDefault(): Converged due to small update length: 2.704975022914e+04 < 1.000000000000e-05 * 3.702469482296e+09
> 4 2r: 5.44E-01 2x: 3.70E+09 2u: 2.70E+04 ir: 3.84E-01 iu: 2.34E+04 rsn: stol
> Nonlinear flow_ solve converged due to CONVERGED_SNORM_RELATIVE iterations 4
>
>
> As the simulation advances this behaviour leads to frequent time step cuts because of 8 subsequently failed Newton iterations, which brings the simulation practically to a halt.
>
> Is the Block Jacobi not a good choice? Better ASM with huge overlap? Or is there something wrong with my RHS? Maybe the SNES, SNESLS, KSP tolerances need better tuning?
>
> Grateful for any clarifying words!
> Robert
>
>
> My SNES_view is:
>
>
> SNES Object: (flow_) 2 MPI processes
> type: newtonls
> maximum iterations=8, maximum function evaluations=10000
> tolerances: relative=1e-05, absolute=1e-05, solution=1e-05
> total number of linear solver iterations=1
> total number of function evaluations=2
> norm schedule ALWAYS
> SNESLineSearch Object: (flow_) 2 MPI processes
> type: basic
> maxstep=1.000000e+08, minlambda=1.000000e-05
> tolerances: relative=1.000000e-05, absolute=1.000000e-05, lambda=1.000000e-08
> maximum iterations=40
> using user-defined precheck step
> KSP Object: (flow_) 2 MPI processes
> type: fgmres
> GMRES: restart=30, using Classical (unmodified) Gram-Schmidt Orthogonalization with no iterative refinement
> GMRES: happy breakdown tolerance 1e-30
> maximum iterations=200, initial guess is zero
> tolerances: relative=1e-07, absolute=1e-50, divergence=10000.
> right preconditioning
> using UNPRECONDITIONED norm type for convergence test
> PC Object: (flow_) 2 MPI processes
> type: composite
> Composite PC type - MULTIPLICATIVE
> PCs on composite preconditioner follow
> ---------------------------------
> PC Object: (flow_sub_0_) 2 MPI processes
> type: galerkin
> Galerkin PC
> KSP on Galerkin follow
> ---------------------------------
> KSP Object: (flow_sub_0_galerkin_) 2 MPI processes
> type: gmres
> GMRES: restart=30, using Classical (unmodified) Gram-Schmidt Orthogonalization with no iterative refinement
> GMRES: happy breakdown tolerance 1e-30
> maximum iterations=200, initial guess is zero
> tolerances: relative=1e-07, absolute=1e-50, divergence=10000.
> left preconditioning
> using PRECONDITIONED norm type for convergence test
> PC Object: (flow_sub_0_galerkin_) 2 MPI processes
> type: hypre
> HYPRE BoomerAMG preconditioning
> HYPRE BoomerAMG: Cycle type V
> HYPRE BoomerAMG: Maximum number of levels 25
> HYPRE BoomerAMG: Maximum number of iterations PER hypre call 1
> HYPRE BoomerAMG: Convergence tolerance PER hypre call 0.
> HYPRE BoomerAMG: Threshold for strong coupling 0.25
> HYPRE BoomerAMG: Interpolation truncation factor 0.
> HYPRE BoomerAMG: Interpolation: max elements per row 0
> HYPRE BoomerAMG: Number of levels of aggressive coarsening 0
> HYPRE BoomerAMG: Number of paths for aggressive coarsening 1
> HYPRE BoomerAMG: Maximum row sums 0.9
> HYPRE BoomerAMG: Sweeps down 1
> HYPRE BoomerAMG: Sweeps up 1
> HYPRE BoomerAMG: Sweeps on coarse 1
> HYPRE BoomerAMG: Relax down symmetric-SOR/Jacobi
> HYPRE BoomerAMG: Relax up symmetric-SOR/Jacobi
> HYPRE BoomerAMG: Relax on coarse Gaussian-elimination
> HYPRE BoomerAMG: Relax weight (all) 1.
> HYPRE BoomerAMG: Outer relax weight (all) 1.
> HYPRE BoomerAMG: Using CF-relaxation
> HYPRE BoomerAMG: Not using more complex smoothers.
> HYPRE BoomerAMG: Measure type local
> HYPRE BoomerAMG: Coarsen type Falgout
> HYPRE BoomerAMG: Interpolation type classical
> linear system matrix = precond matrix:
> Mat Object: 2 MPI processes
> type: mpiaij
> rows=8000, cols=8000
> total: nonzeros=53600, allocated nonzeros=53600
> total number of mallocs used during MatSetValues calls =0
> not using I-node (on process 0) routines
> linear system matrix = precond matrix:
> Mat Object: (flow_) 2 MPI processes
> type: mpibaij
> rows=24000, cols=24000, bs=3
> total: nonzeros=482400, allocated nonzeros=482400
> total number of mallocs used during MatSetValues calls =0
> PC Object: (flow_sub_1_) 2 MPI processes
> type: bjacobi
> block Jacobi: number of blocks = 2
> Local solve is same for all blocks, in the following KSP and PC objects:
> KSP Object: (flow_sub_1_sub_) 1 MPI processes
> type: preonly
> maximum iterations=10000, initial guess is zero
> tolerances: relative=1e-05, absolute=1e-50, divergence=10000. <------ not working: -flow_sub_1_sub_ksp_rtol 1e-7
> left preconditioning
> using NONE norm type for convergence test
> PC Object: (flow_sub_1_sub_) 1 MPI processes
> type: lu
> out-of-place factorization
> tolerance for zero pivot 2.22045e-14
> matrix ordering: nd
> factor fill ratio given 5., needed 18.3108
> Factored matrix follows:
> Mat Object: 1 MPI processes
> type: seqbaij
> rows=12000, cols=12000, bs=3
> package used to perform factorization: petsc
> total: nonzeros=4350654, allocated nonzeros=4350654
> total number of mallocs used during MatSetValues calls =0
> block size is 3
> linear system matrix = precond matrix:
> Mat Object: (flow_) 1 MPI processes
> type: seqbaij
> rows=12000, cols=12000, bs=3
> total: nonzeros=237600, allocated nonzeros=237600
> total number of mallocs used during MatSetValues calls =0
> block size is 3
> linear system matrix = precond matrix:
> Mat Object: (flow_) 2 MPI processes
> type: mpibaij
> rows=24000, cols=24000, bs=3
> total: nonzeros=482400, allocated nonzeros=482400
> total number of mallocs used during MatSetValues calls =0
> ---------------------------------
> linear system matrix = precond matrix:
> Mat Object: (flow_) 2 MPI processes
> type: mpibaij
> rows=24000, cols=24000, bs=3
> total: nonzeros=482400, allocated nonzeros=482400
> total number of mallocs used during MatSetValues calls =0
More information about the petsc-users
mailing list