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<p>Hi Matthew,</p>
<p>is it possible to do in principle what I would like to do?</p>
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<div class="moz-cite-prefix">On 9/25/2019 3:12 AM, Matthew Knepley wrote:<br>
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<div dir="ltr">On Wed, Sep 25, 2019 at 1:27 AM Povolotskyi, Mykhailo via petsc-users <<a href="mailto:petsc-users@mcs.anl.gov" moz-do-not-send="true">petsc-users@mcs.anl.gov</a>> wrote:<br>
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Dear Petsc developers,<br>
<br>
in my application I have to solve millions of linear and non-linear <br>
systems with small matrices (2x2, 3x3,..., 10x10).<br>
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I consider them as dense, and use SNES with KSP method PREONLY, and LU <br>
preconditioner.<br>
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I found that when KSPSolve is called only 25% of time is spend in <br>
lapack, the rest is PETSc overhead.<br>
<br>
I know how to call lapack directly to solve a linear system.<br>
<br>
Question: is it possible to call lapack directly in the SNES solver to <br>
avoid the KSPSolve overhead?<br>
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<div>Question: Do you solve a bunch of them simultaneously?</div>
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<div> Thanks,</div>
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<div> Matt</div>
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Thank you,<br>
<br>
Michael.<br>
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-- <br>
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<div>What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead.<br>
-- Norbert Wiener</div>
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<div><a href="http://www.cse.buffalo.edu/~knepley/" target="_blank" moz-do-not-send="true">https://www.cse.buffalo.edu/~knepley/</a><br>
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