<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=utf-8">
</head>
<body text="#000000" bgcolor="#FFFFFF">
<p>Hi, I had the idea to try and renumber my mesh cells, as I've
heard it's better: "neighbouring cells are stored next to one
another, and memory access are faster".</p>
Right now, I load the mesh then I distribute it over the processes.
I thought I'd try to permute the numbering between those two steps :<br>
<blockquote><tt>DMPlexCreateFromFile</tt><tt><br>
</tt><tt>DMPlexGetOrdering</tt><tt><br>
</tt><tt>DMPlexPermute</tt><tt><br>
</tt><tt>DMPlexDistribute</tt></blockquote>
<p>but that gives me an error when it runs on more than one process:</p>
<p><tt>[0]PETSC ERROR: --------------------- Error Message
--------------------------------------------------------------</tt><tt><br>
</tt><tt>[0]PETSC ERROR: No support for this operation for this
object type</tt><tt><br>
</tt><tt>[0]PETSC ERROR: Number of dofs for point 0 in the local
section should be positive</tt><tt><br>
</tt><tt>[0]PETSC ERROR: See <a class="moz-txt-link-freetext" href="https://petsc.org/release/faq/">https://petsc.org/release/faq/</a> for
trouble shooting.</tt><tt><br>
</tt><tt>[0]PETSC ERROR: Petsc Release Version 3.16.0, unknown </tt><tt><br>
</tt><tt>[0]PETSC ERROR: ./build/bin/yanss on a named
ldmpe202z.onera by pseize Tue Oct 26 16:03:33 2021</tt><tt><br>
</tt><tt>[0]PETSC ERROR: Configure options
--PETSC_ARCH=arch-ld-gcc --download-metis --download-parmetis
--prefix=~/.local --with-cgns</tt><tt><br>
</tt><tt>[0]PETSC ERROR: #1 PetscPartitionerDMPlexPartition() at
/stck/pseize/softwares/petsc/src/dm/impls/plex/plexpartition.c:720</tt><tt><br>
</tt><tt>[0]PETSC ERROR: #2 DMPlexDistribute() at
/stck/pseize/softwares/petsc/src/dm/impls/plex/plexdistribute.c:1630</tt><tt><br>
</tt><tt>[0]PETSC ERROR: #3 MeshLoadFromFile() at
src/spatial.c:689</tt><tt><br>
</tt><tt>[0]PETSC ERROR: #4 main() at src/main.c:22</tt><tt><br>
</tt><tt>[0]PETSC ERROR: PETSc Option Table entries:</tt><tt><br>
</tt><tt>[0]PETSC ERROR: -draw_comp 0</tt><tt><br>
</tt><tt>[0]PETSC ERROR: -mesh data/box.msh</tt><tt><br>
</tt><tt>[0]PETSC ERROR: -mesh_view draw</tt><tt><br>
</tt><tt>[0]PETSC ERROR: -riemann anrs</tt><tt><br>
</tt><tt>[0]PETSC ERROR: -ts_max_steps 100</tt><tt><br>
</tt><tt>[0]PETSC ERROR: -vec_view_partition</tt><tt><br>
</tt><tt>[0]PETSC ERROR: ----------------End of Error Message
-------send entire error message to
<a class="moz-txt-link-abbreviated" href="mailto:petsc-maint@mcs.anl.gov">petsc-maint@mcs.anl.gov</a>----------</tt><br>
<br>
</p>
<p>I checked and before I tried to reorder the mesh, the <tt>dm-></tt><tt>localSection</tt>
was <tt>NULL</tt> before entering <tt>DMPlexDistribute</tt>, and
I was able to fix the error with <tt>DMSetLocalSection(dm, NULL)</tt>
after <tt>DMPlexPermute</tt>, but it doesn't seems it's the right
way to do what I want. Does someone have any advice ?</p>
<p>Thanks in advance</p>
<p>Pierre Seize<br>
</p>
</body>
</html>