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<div style="direction: ltr;font-family: Arial;color: #000000;font-size: 14pt;">Thanks. I'll give these try. It is interesting to look at your results for the<br>
3d ice flow problem.<br>
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Thanks,<br>
<br>
Dave<br>
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<div style="font-family: Tahoma; font-size: 13px;"><font size="2"><span style="font-size: 10pt;">--
<br>
Dave Nystrom<br>
LANL HPC-5<br>
Phone: 505-667-7913<br>
Email: wdn@lanl.gov<br>
Smail: Mail Stop B272<br>
Group HPC-5<br>
Los Alamos National Laboratory<br>
Los Alamos, NM 87545<br>
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<div style="direction: ltr;" id="divRpF74559"><font color="#000000" face="Tahoma" size="2"><b>From:</b> petsc-dev-bounces@mcs.anl.gov [petsc-dev-bounces@mcs.anl.gov] on behalf of Jed Brown [jedbrown@mcs.anl.gov]<br>
<b>Sent:</b> Friday, January 20, 2012 3:12 PM<br>
<b>To:</b> For users of the development version of PETSc<br>
<b>Subject:</b> Re: [petsc-dev] Test Problem Recommendations<br>
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<div class="gmail_quote">On Fri, Jan 20, 2012 at 16:03, Nystrom, William D <span dir="ltr">
<<a href="mailto:wdn@lanl.gov" target="_blank">wdn@lanl.gov</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<div id=":4ye">I'm getting ready to use petsc-dev as part of our test suite for doing<br>
stability testing of some new hardware platforms with gpus. I'm<br>
interested in testing both with and without using gpus. So far, I have<br>
not extensively explored the various example problems that come with<br>
PETSc. Mainly, I have run src/ksp/ksp/examples/tutorials/ex2.c<br>
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<div>This is a horrible example because the parallel decomposition is 1D. You can run essentially the same model with a better decomposition (and inside a nonlinear problem) with src/snes/examples/tutorials/ex5.c (which can also do geometric multigrid, but
you don't have to use it).</div>
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<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<div id=":4ye">which is a 2d Laplace's equation problem. I'm looking for recommendations<br>
of PETSc example problems that I should try, especially ones that might<br>
be more challenging numerically than ex2.c or more realistic of real<br>
world problems. Does anyone reading this email have a favorite PETSc<br>
example problem that you would suggest I consider and try?</div>
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<div>Here are some options and profiling output (on a BG/P) for a 3D ice flow problem (src/snes/examples/tutorials/ex48.c):</div>
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<div><a href="https://github.com/jedbrown/tme-ice/tree/master/shaheen/b" target="_blank">https://github.com/jedbrown/tme-ice/tree/master/shaheen/b</a></div>
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<div>src/ksp/ksp/examples/tutorials/ex43.c (2D Stokes, preconditioned using fieldsplit inside multigrid)</div>
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<div>mpiexec -n 8 ./ex43 -stokes_ksp_type gcr -stokes_ksp_gcr_restart 60 -stokes_ksp_norm_type unpreconditioned -stokes_ksp_rtol 1e-8 -c_str 3 -sinker_eta0 1.0 -sinker_eta1 100 -sinker_dx 0.4 -sinker_dy 0.3 -mx 1024 -my 1024 -stokes_ksp_monitor -o sc1024.dat
-stokes_pc_type mg -stokes_mg_levels_pc_type fieldsplit -stokes_pc_mg_galerkin -stokes_mg_levels_pc_fieldsplit_block_size 3 -stokes_mg_levels_pc_fieldsplit_0_fields 0,1 -stokes_mg_levels_pc_fieldsplit_1_fields 2 -stokes_mg_levels_fieldsplit_0_pc_type sor -stokes_mg_levels_ksp_type
chebychev -stokes_mg_levels_ksp_max_it 1 -stokes_mg_levels_ksp_chebychev_estimate_eigenvalues 0,0.2,0,1.1 -stokes_pc_mg_levels 5 -log_summary</div>
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<div>src/ksp/ksp/examples/tutorials/ex56.c (3D elasticity, process count should be 8^n)</div>
<div>mpiexec -n 64 ./ex56 -ne 255 -alpha 1.e-3 -ksp_monitor_short -ksp_type cg -pc_gamg_type sa -ksp_norm_type unpreconditioned -pc_gamg_verbose -pc_gamg_repartition -pc_gamg_process_eq_limit 10 -pc_gamg_coarse_eq_limit 20 -pc_gamg_mat_partitioning_type ptscotch
-log_summary -pc_gamg_mat_partitioning_ptscotch_strategy scalability</div>
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