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<p class="MsoNormal">Hello PETSc users community,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Happy new year! Thank you for the community support as always.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I am using BoomerAMG for my research, and it is interfaced to my software via PETSc. I can only use options database keys as of now to tweak the settings I want for the AMG solve.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I want to control the number of smoothener iterations at pre/post step for a given AMG cycle. I am looking for an options database key which helps me control this. I am not sure whether this is possible directly via the keys (Line 365:
<a href="https://www.mcs.anl.gov/petsc/petsc-3.5.4/src/ksp/pc/impls/hypre/hypre.c.html">
https://www.mcs.anl.gov/petsc/petsc-3.5.4/src/ksp/pc/impls/hypre/hypre.c.html</a>). My comprehension of the current setup is that I have 1 smoothener iteration at every coarsening step. My aim is to do two pre and 2 post smoothening steps using the SSOR smoothener.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoPlainText">BoomerAMG SOLVER PARAMETERS:<o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText"> Maximum number of cycles: 1 <o:p></o:p></p>
<p class="MsoPlainText"> Stopping Tolerance: 0.000000e+00 <o:p></o:p></p>
<p class="MsoPlainText"> Cycle type (1 = V, 2 = W, etc.): 1<o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText"> Relaxation Parameters:<o:p></o:p></p>
<p class="MsoPlainText"> Visiting Grid: down up coarse<o:p></o:p></p>
<p class="MsoPlainText"> Number of sweeps: 1 1 1 <o:p>
</o:p></p>
<p class="MsoPlainText"> Type 0=Jac, 3=hGS, 6=hSGS, 9=GE: 6 6 9 <o:p>
</o:p></p>
<p class="MsoPlainText"> Point types, partial sweeps (1=C, -1=F):<o:p></o:p></p>
<p class="MsoPlainText"> Pre-CG relaxation (down): 1 -1<o:p></o:p></p>
<p class="MsoPlainText"> Post-CG relaxation (up): -1 1<o:p></o:p></p>
<p class="MsoPlainText"> Coarsest grid: 0<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">PETSC settings I am using currently: <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">-ksp_type preonly<o:p></o:p></p>
<p class="MsoNormal">-pc_type hypre<o:p></o:p></p>
<p class="MsoNormal">-pc_hypre_type boomeramg<o:p></o:p></p>
<p class="MsoNormal">-pc_hypre_boomeramg_coarsen_type hmis<o:p></o:p></p>
<p class="MsoNormal">-pc_hypre_boomeramg_relax_type_all symmetric-sor/jacobi<o:p></o:p></p>
<p class="MsoNormal">-pc_hypre_boomeramg_strong_threshold 0.7<o:p></o:p></p>
<p class="MsoNormal">-pc_hypre_boomeramg_interp_type ext+i<o:p></o:p></p>
<p class="MsoNormal">-pc_hypre_boomeramg_P_max 2<o:p></o:p></p>
<p class="MsoNormal">-pc_hypre_boomeramg_truncfactor 0.3<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks and Best<o:p></o:p></p>
<p class="MsoNormal">Parv Khurana<o:p></o:p></p>
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