You can subscribe to this list here.
2003 
_{Jan}

_{Feb}

_{Mar}

_{Apr}

_{May}

_{Jun}

_{Jul}

_{Aug}

_{Sep}
(2) 
_{Oct}
(2) 
_{Nov}
(27) 
_{Dec}
(31) 

2004 
_{Jan}
(6) 
_{Feb}
(15) 
_{Mar}
(33) 
_{Apr}
(10) 
_{May}
(46) 
_{Jun}
(11) 
_{Jul}
(21) 
_{Aug}
(15) 
_{Sep}
(13) 
_{Oct}
(23) 
_{Nov}
(1) 
_{Dec}
(8) 
2005 
_{Jan}
(27) 
_{Feb}
(57) 
_{Mar}
(86) 
_{Apr}
(23) 
_{May}
(37) 
_{Jun}
(34) 
_{Jul}
(24) 
_{Aug}
(17) 
_{Sep}
(50) 
_{Oct}
(24) 
_{Nov}
(10) 
_{Dec}
(60) 
2006 
_{Jan}
(47) 
_{Feb}
(46) 
_{Mar}
(127) 
_{Apr}
(19) 
_{May}
(26) 
_{Jun}
(62) 
_{Jul}
(47) 
_{Aug}
(51) 
_{Sep}
(61) 
_{Oct}
(42) 
_{Nov}
(50) 
_{Dec}
(33) 
2007 
_{Jan}
(60) 
_{Feb}
(55) 
_{Mar}
(77) 
_{Apr}
(102) 
_{May}
(82) 
_{Jun}
(102) 
_{Jul}
(169) 
_{Aug}
(117) 
_{Sep}
(80) 
_{Oct}
(37) 
_{Nov}
(51) 
_{Dec}
(43) 
2008 
_{Jan}
(71) 
_{Feb}
(94) 
_{Mar}
(98) 
_{Apr}
(125) 
_{May}
(54) 
_{Jun}
(119) 
_{Jul}
(60) 
_{Aug}
(111) 
_{Sep}
(118) 
_{Oct}
(125) 
_{Nov}
(119) 
_{Dec}
(94) 
2009 
_{Jan}
(109) 
_{Feb}
(38) 
_{Mar}
(93) 
_{Apr}
(88) 
_{May}
(29) 
_{Jun}
(57) 
_{Jul}
(53) 
_{Aug}
(48) 
_{Sep}
(68) 
_{Oct}
(151) 
_{Nov}
(23) 
_{Dec}
(35) 
2010 
_{Jan}
(84) 
_{Feb}
(60) 
_{Mar}
(184) 
_{Apr}
(112) 
_{May}
(60) 
_{Jun}
(90) 
_{Jul}
(23) 
_{Aug}
(70) 
_{Sep}
(119) 
_{Oct}
(27) 
_{Nov}
(47) 
_{Dec}
(54) 
2011 
_{Jan}
(22) 
_{Feb}
(19) 
_{Mar}
(92) 
_{Apr}
(93) 
_{May}
(35) 
_{Jun}
(91) 
_{Jul}
(32) 
_{Aug}
(61) 
_{Sep}
(7) 
_{Oct}
(69) 
_{Nov}
(81) 
_{Dec}
(23) 
2012 
_{Jan}
(64) 
_{Feb}
(95) 
_{Mar}
(35) 
_{Apr}
(36) 
_{May}
(63) 
_{Jun}
(98) 
_{Jul}
(70) 
_{Aug}
(171) 
_{Sep}
(149) 
_{Oct}
(64) 
_{Nov}
(67) 
_{Dec}
(126) 
2013 
_{Jan}
(108) 
_{Feb}
(104) 
_{Mar}
(171) 
_{Apr}
(133) 
_{May}
(108) 
_{Jun}
(100) 
_{Jul}
(93) 
_{Aug}
(126) 
_{Sep}
(74) 
_{Oct}
(59) 
_{Nov}
(145) 
_{Dec}
(93) 
2014 
_{Jan}
(38) 
_{Feb}
(45) 
_{Mar}
(26) 
_{Apr}
(41) 
_{May}
(125) 
_{Jun}
(70) 
_{Jul}
(61) 
_{Aug}
(66) 
_{Sep}
(60) 
_{Oct}
(110) 
_{Nov}
(27) 
_{Dec}
(30) 
2015 
_{Jan}
(43) 
_{Feb}
(67) 
_{Mar}
(71) 
_{Apr}
(92) 
_{May}
(39) 
_{Jun}
(15) 
_{Jul}
(46) 
_{Aug}
(63) 
_{Sep}
(84) 
_{Oct}
(82) 
_{Nov}
(69) 
_{Dec}
(45) 
2016 
_{Jan}
(92) 
_{Feb}
(91) 
_{Mar}
(148) 
_{Apr}
(43) 
_{May}
(58) 
_{Jun}
(117) 
_{Jul}
(92) 
_{Aug}
(140) 
_{Sep}
(49) 
_{Oct}
(33) 
_{Nov}
(85) 
_{Dec}
(40) 
2017 
_{Jan}
(41) 
_{Feb}
(36) 
_{Mar}
(49) 
_{Apr}
(41) 
_{May}
(73) 
_{Jun}
(51) 
_{Jul}
(12) 
_{Aug}
(69) 
_{Sep}
(26) 
_{Oct}
(43) 
_{Nov}
(68) 
_{Dec}

S  M  T  W  T  F  S 

1
(7) 
2
(3) 
3
(4) 
4
(10) 
5
(27) 
6
(7) 
7
(2) 
8

9
(7) 
10
(12) 
11
(1) 
12
(3) 
13

14
(1) 
15
(1) 
16
(1) 
17

18

19
(2) 
20

21

22

23
(1) 
24

25

26

27

28
(2) 
29

30
(2) 
31





From: Dmitry Karpeyev <karpeev@mc...>  20131209 22:03:54

Please, include snes_view so that we can see exactly what solver options are being used. Dmitry. On Mon, Dec 9, 2013 at 12:48 PM, John Peterson <jwpeterson@...> wrote: > > On Mon, Dec 9, 2013 at 11:31 AM, Lorenzo Zanon > > <zanon@...>wrote: > > > >> I get faster convergence with e.g. snes_linesearch_type basic ksp_rtol > >> 1e4: > >> > >> NL step 0, residual_2 = 3.464102e05 > >> NL step 1, residual_2 = 2.417540e04 > >> NL step 2, residual_2 = 6.174706e08 > >> NL step 3, residual_2 = 3.577768e12 > >> NL step 4, residual_2 = 7.687278e17 > >> StVen system solved at nonlinear iteration 4 , final nonlinear residual > >> norm: 7.687278e17 > > Your ksp_rtol might be hurting your convergence a bit near the root... > > Have you tried snes_ksp_ew? There are several EWspecific options > within you can play with as well: > > > http://www.mcs.anl.gov/petsc/petsccurrent/docs/manualpages/SNES/SNESSetFromOptions.html > >  > John > > >  > Sponsored by Intel(R) XDK > Develop, test and display web and hybrid apps with a single code base. > Download it for free now! > > http://pubads.g.doubleclick.net/gampad/clk?id=111408631&iu=/4140/ostg.clktrk > _______________________________________________ > Libmeshusers mailing list > Libmeshusers@... > https://lists.sourceforge.net/lists/listinfo/libmeshusers >  Dmitry Karpeev Mathematics and Computer Science Argonne National Laboratory Argonne, Illinois, USA and Computation Institute University of Chicago 5735 S. Ellis Avenue Chicago, IL 60637  Phone: 6302521229 Fax: 6302525986 
From: John Peterson <jwpeterson@gm...>  20131209 18:49:21

> On Mon, Dec 9, 2013 at 11:31 AM, Lorenzo Zanon > <zanon@...>wrote: > >> I get faster convergence with e.g. snes_linesearch_type basic ksp_rtol >> 1e4: >> >> NL step 0, residual_2 = 3.464102e05 >> NL step 1, residual_2 = 2.417540e04 >> NL step 2, residual_2 = 6.174706e08 >> NL step 3, residual_2 = 3.577768e12 >> NL step 4, residual_2 = 7.687278e17 >> StVen system solved at nonlinear iteration 4 , final nonlinear residual >> norm: 7.687278e17 Your ksp_rtol might be hurting your convergence a bit near the root... Have you tried snes_ksp_ew? There are several EWspecific options within you can play with as well: http://www.mcs.anl.gov/petsc/petsccurrent/docs/manualpages/SNES/SNESSetFromOptions.html  John 
From: Derek Gaston <friedmud@gm...>  20131209 18:34:52

Good to hear Lorenzo! How many linear iterations are you taking? (use ksp_monitor to see) You might be able to get better performance using a better preconditioner... I still highly recommend trying Hypre... Derek On Mon, Dec 9, 2013 at 11:31 AM, Lorenzo Zanon <zanon@...>wrote: > Hello, > > I'm sorry it took so long. > > There were actually a couple of mistakes in my jacobian and residual. > > Now for the small problem without specifying any options I get: > > Running ./exampleopt > > Mesh Information: > mesh_dimension()=3 > spatial_dimension()=3 > n_nodes()=66 > n_local_nodes()=66 > n_elem()=20 > n_local_elem()=20 > n_active_elem()=20 > n_subdomains()=1 > n_partitions()=1 > n_processors()=1 > n_threads()=1 > processor_id()=0 > > EquationSystems > n_systems()=1 > System #0, "StVen" > Type "NonlinearImplicit" > Variables={ "u" "v" "z" } > Finite Element Types="LAGRANGE" > Approximation Orders="FIRST" > n_dofs()=198 > n_local_dofs()=198 > n_constrained_dofs()=18 > n_local_constrained_dofs()=18 > n_vectors()=1 > n_matrices()=1 > DofMap Sparsity > Average OnProcessor Bandwidth <= 39.4545 > Average OffProcessor Bandwidth <= 0 > Maximum OnProcessor Bandwidth <= 54 > Maximum OffProcessor Bandwidth <= 0 > DofMap Constraints > Number of DoF Constraints = 18 > Average DoF Constraint Length= 0 > > NL step 0, residual_2 = 3.464102e05 > NL step 1, residual_2 = 3.126867e05 > NL step 2, residual_2 = 2.835742e05 > NL step 3, residual_2 = 2.579682e05 > NL step 4, residual_2 = 2.351091e05 > NL step 5, residual_2 = 2.144758e05 > NL step 6, residual_2 = 1.957083e05 > NL step 7, residual_2 = 1.785531e05 > NL step 8, residual_2 = 1.628262e05 > NL step 9, residual_2 = 1.463259e05 > NL step 10, residual_2 = 1.280174e05 > NL step 11, residual_2 = 1.073276e05 > NL step 12, residual_2 = 8.355152e06 > NL step 13, residual_2 = 7.606801e06 > NL step 14, residual_2 = 9.503420e11 > NL step 15, residual_2 = 2.354762e15 > StVen system solved at nonlinear iteration 15 , final nonlinear residual > norm: 2.354762e15 > > > I get faster convergence with e.g. snes_linesearch_type basic ksp_rtol > 1e4: > > NL step 0, residual_2 = 3.464102e05 > NL step 1, residual_2 = 2.417540e04 > NL step 2, residual_2 = 6.174706e08 > NL step 3, residual_2 = 3.577768e12 > NL step 4, residual_2 = 7.687278e17 > StVen system solved at nonlinear iteration 4 , final nonlinear residual > norm: 7.687278e17 > > > I think it would be fine to use these last options also on a finer mesh > then. It finally looks like I don't need JFNK. > > Thanks! > Lorenzo > > On Nov 26, 2013, at 8:42 PM, Derek Gaston wrote: > > On Tue, Nov 26, 2013 at 11:59 AM, Dmitry Karpeyev <karpeev@...>wrote: > >> LU, naturally, should do better, and we should at least see quicker >> linear convergence. >> If not, it's an indication that your problem is singular. >> > > LU should only take 1 (ish) linear iteration. > > However, I still suspect that the issue here is that his Jacobian is > wrong... which accounts for the degraded nonlinear convergence. > > Lorenzo: Have you double checked your Jacobian statements? Have you > checked them against your friend doing FEAP? Your statements should look > very similar to theirs... > > Derek > > > 
From: Lorenzo Zanon <zanon@ai...>  20131209 18:32:07

Hello, I'm sorry it took so long. There were actually a couple of mistakes in my jacobian and residual. Now for the small problem without specifying any options I get: > Running ./exampleopt > > Mesh Information: > mesh_dimension()=3 > spatial_dimension()=3 > n_nodes()=66 > n_local_nodes()=66 > n_elem()=20 > n_local_elem()=20 > n_active_elem()=20 > n_subdomains()=1 > n_partitions()=1 > n_processors()=1 > n_threads()=1 > processor_id()=0 > > EquationSystems > n_systems()=1 > System #0, "StVen" > Type "NonlinearImplicit" > Variables={ "u" "v" "z" } > Finite Element Types="LAGRANGE" > Approximation Orders="FIRST" > n_dofs()=198 > n_local_dofs()=198 > n_constrained_dofs()=18 > n_local_constrained_dofs()=18 > n_vectors()=1 > n_matrices()=1 > DofMap Sparsity > Average OnProcessor Bandwidth <= 39.4545 > Average OffProcessor Bandwidth <= 0 > Maximum OnProcessor Bandwidth <= 54 > Maximum OffProcessor Bandwidth <= 0 > DofMap Constraints > Number of DoF Constraints = 18 > Average DoF Constraint Length= 0 > > NL step 0, residual_2 = 3.464102e05 > NL step 1, residual_2 = 3.126867e05 > NL step 2, residual_2 = 2.835742e05 > NL step 3, residual_2 = 2.579682e05 > NL step 4, residual_2 = 2.351091e05 > NL step 5, residual_2 = 2.144758e05 > NL step 6, residual_2 = 1.957083e05 > NL step 7, residual_2 = 1.785531e05 > NL step 8, residual_2 = 1.628262e05 > NL step 9, residual_2 = 1.463259e05 > NL step 10, residual_2 = 1.280174e05 > NL step 11, residual_2 = 1.073276e05 > NL step 12, residual_2 = 8.355152e06 > NL step 13, residual_2 = 7.606801e06 > NL step 14, residual_2 = 9.503420e11 > NL step 15, residual_2 = 2.354762e15 > StVen system solved at nonlinear iteration 15 , final nonlinear residual norm: 2.354762e15 I get faster convergence with e.g. snes_linesearch_type basic ksp_rtol 1e4: > NL step 0, residual_2 = 3.464102e05 > NL step 1, residual_2 = 2.417540e04 > NL step 2, residual_2 = 6.174706e08 > NL step 3, residual_2 = 3.577768e12 > NL step 4, residual_2 = 7.687278e17 > StVen system solved at nonlinear iteration 4 , final nonlinear residual norm: 7.687278e17 I think it would be fine to use these last options also on a finer mesh then. It finally looks like I don't need JFNK. Thanks! Lorenzo On Nov 26, 2013, at 8:42 PM, Derek Gaston wrote: > On Tue, Nov 26, 2013 at 11:59 AM, Dmitry Karpeyev <karpeev@...> wrote: > LU, naturally, should do better, and we should at least see quicker linear convergence. > If not, it's an indication that your problem is singular. > > LU should only take 1 (ish) linear iteration. > > However, I still suspect that the issue here is that his Jacobian is wrong... which accounts for the degraded nonlinear convergence. > > Lorenzo: Have you double checked your Jacobian statements? Have you checked them against your friend doing FEAP? Your statements should look very similar to theirs... > > Derek 
From: Subramanya Sadasiva <potaman@ou...>  20131209 17:28:23

I had attached a picture. The system is not updating itself. So i get these cracklike discontinuities in the solution, with the number of sections equal to the number of processors. On Dec 9, 2013, at 12:17 PM, Derek Gaston <friedmud@...> wrote: > How is it failing in parallel? Is it not converging, or something else? > > What preconditioner are you using? How well are the linear solves going (use ksp_monitor)? > > Derek > > > > On Mon, Dec 9, 2013 at 9:59 AM, subramanya sadasiva <potaman@...> wrote: > Hi, > i am trying to run a nonlinear solver (a multiphase cahn hilliard) with 4 variables (3 phases  so two phase and two chemical potentials). The code seems to be doing fine on one processor, however, it is failing miserably in parallel. I get the following divisions, always equal to the number of processors that I am running on. I only use current_local_solution and old_local_solution to construct the jacobians and residuals, so the vectors should be properly ghosted. These divisions remain even if I call update on the system again. Any ideas?Thanks, Subramanya > >  > Sponsored by Intel(R) XDK > Develop, test and display web and hybrid apps with a single code base. > Download it for free now! > http://pubads.g.doubleclick.net/gampad/clk?id=111408631&iu=/4140/ostg.clktrk > _______________________________________________ > Libmeshusers mailing list > Libmeshusers@... > https://lists.sourceforge.net/lists/listinfo/libmeshusers > > 
From: Derek Gaston <friedmud@gm...>  20131209 17:17:23

How is it failing in parallel? Is it not converging, or something else? What preconditioner are you using? How well are the linear solves going (use ksp_monitor)? Derek On Mon, Dec 9, 2013 at 9:59 AM, subramanya sadasiva <potaman@...>wrote: > Hi, > i am trying to run a nonlinear solver (a multiphase cahn hilliard) with 4 > variables (3 phases  so two phase and two chemical potentials). The code > seems to be doing fine on one processor, however, it is failing miserably > in parallel. I get the following divisions, always equal to the number of > processors that I am running on. I only use current_local_solution and > old_local_solution to construct the jacobians and residuals, so the vectors > should be properly ghosted. These divisions remain even if I call update > on the system again. Any ideas?Thanks, Subramanya > > >  > Sponsored by Intel(R) XDK > Develop, test and display web and hybrid apps with a single code base. > Download it for free now! > > http://pubads.g.doubleclick.net/gampad/clk?id=111408631&iu=/4140/ostg.clktrk > _______________________________________________ > Libmeshusers mailing list > Libmeshusers@... > https://lists.sourceforge.net/lists/listinfo/libmeshusers > > 
From: subramanya sadasiva <potaman@ou...>  20131209 17:00:03

Hi, i am trying to run a nonlinear solver (a multiphase cahn hilliard) with 4 variables (3 phases  so two phase and two chemical potentials). The code seems to be doing fine on one processor, however, it is failing miserably in parallel. I get the following divisions, always equal to the number of processors that I am running on. I only use current_local_solution and old_local_solution to construct the jacobians and residuals, so the vectors should be properly ghosted. These divisions remain even if I call update on the system again. Any ideas?Thanks, Subramanya 