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<div dir="ltr">Edoardo:<br>
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<div>You can test runtime option '-sub_pc_factor_mat_ordering_type' and use '-log_view' to get performance on different orderings, e.g.,petsc/src/ksp/ksp/examples/tutorials/ex2.c:</div>
<div>mpiexec -n 2 ./ex2 -ksp_view -sub_pc_type ilu -sub_pc_factor_mat_ordering_type nd<br>
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<div>I do not think the ordering inside block for ilu would affect performance much. Let us know what you will get.</div>
<div>Hong</div>
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<div>Dear users, </div>
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<div>I have a question about the correct use of the option "PCFactorSetMatOrderingType" in PETSc. </div>
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<div>I am solving a problem with 2.5M of unknowns distributed along 16 processors and I am using the block jacobi preconditioner and MPIAIJ matrix format. I cannot figure out if the above option can be useful or not in decreasing the computational time. Any
suggestion or tips?</div>
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<div>Thank you very much for the kind help </div>
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<div>Edoardo Alinovi, Ph.D.</div>
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<div>DICCA, Scuola Politecnica<br>
Universita' di Genova<br>
1, via Montallegro<br>
16145 Genova, Italy<br>
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<div>email: <a href="mailto:edoardo.alinovi@dicca.unige.it" target="_blank">edoardo.alinovi@dicca.unige.it</a></div>
<div>Tel: +39 010 353 2540<br>
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