<div dir="ltr"><div dir="ltr">On Mon, Sep 30, 2024 at 6:50 AM Karthikeyan Chockalingam - STFC UKRI via petsc-users <<a href="mailto:petsc-users@mcs.anl.gov">petsc-users@mcs.anl.gov</a>> wrote:<br></div><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div class="msg3858356192935295346">
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<p class="MsoNormal"><span style="font-size:11pt">Hi,<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11pt"><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="font-size:11pt">We have been using PETSc’s block version of the AIJ matrix format to implement fully coupled multiphysics problems using finite elements. <u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11pt"><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="font-size:11pt">Are there specific advantages to moving toward DMPlex for finite element-based coupled multi-physics implementation?</span></p></div></div></div></blockquote><div><br></div><div>DMPlex is intended to help manage unstructured grids. It can read/write meshes and functions over them, layout data over the grid</div><div>in parallel, compute local-to-global maps, modify meshes, and also provides some tools for assembling functions and operators.</div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div class="msg3858356192935295346"><div lang="EN-GB" style="overflow-wrap: break-word;"><div class="m_-7931993680594933061WordSection1"><p class="MsoNormal"><span style="font-size:11pt"> Can you still access Hypre?</span></p></div></div></div></blockquote><div><br></div><div>Yes. Hypre interacts with the solvers. DMPlex is only there to help in assembly.</div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div class="msg3858356192935295346"><div lang="EN-GB" style="overflow-wrap: break-word;"><div class="m_-7931993680594933061WordSection1"><p class="MsoNormal"><span style="font-size:11pt"> Does the format support running on GPUs?</span></p></div></div></div></blockquote><div><br></div><div>Running the solver on GPUs is unchanged. However, for assembling on GPUs, there are at least two options:</div><div><br></div><div>1) Do everything yourself using the information provided by DMPlex. This is what Mark does in dmplexland.c for</div><div> assembling the Landau operator. It is hard, but some people can do it.</div><div><br></div><div>2) Use a library. LibCEED is a library for assembling on the GPU, and DMPlex provides support for interacting with it. There</div><div> are DMPlex examples in the LibCEED distribution. This is what I do for assembling on GPUs.</div><div><br></div><div> Thanks,</div><div><br></div><div> Matt</div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div class="msg3858356192935295346"><div lang="EN-GB" style="overflow-wrap: break-word;"><div class="m_-7931993680594933061WordSection1">
<p class="MsoNormal"><span style="font-size:11pt">Thank you.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11pt"><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="font-size:11pt">Kind regards,<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11pt">Karthik.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:11pt"><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="font-size:11pt"><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="font-size:11pt"><u></u> <u></u></span></p>
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<p class="MsoNormal"><span style="font-size:11pt;font-family:Calibri,sans-serif">-- <u></u><u></u></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.5pt;font-family:Arial,sans-serif;color:rgb(45,45,98)">Karthik Chockalingam, Ph.D.<u></u><u></u></span></b></p>
<p class="MsoNormal"><span style="font-size:10.5pt;font-family:Arial,sans-serif;color:black">Senior Research Software Engineer</span><span style="font-size:10.5pt;font-family:Calibri,sans-serif;color:black"><u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:10.5pt;font-family:Arial,sans-serif;color:black">High Performance Systems Engineering Group</span><span style="font-size:10.5pt;font-family:Calibri,sans-serif;color:black"><u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-size:10.5pt;font-family:Arial,sans-serif;color:black">Hartree Centre | Science and Technology Facilities Council</span><span style="font-size:10.5pt;font-family:Calibri,sans-serif;color:black"><u></u><u></u></span></p>
<p class="MsoNormal"><a href="mailto:karthikeyan.chockalingam@stfc.ac.uk" target="_blank"><span style="font-size:10.5pt;font-family:Arial,sans-serif;color:rgb(5,99,193)">karthikeyan.chockalingam@stfc.ac.uk</span></a><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(33,33,33)"><u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-family:"Times New Roman",serif;color:black"> </span><span style="font-size:10.5pt;font-family:Arial,sans-serif;color:rgb(65,65,65)"> </span><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(33,33,33)"><u></u><u></u></span></p>
<p class="MsoNormal"><b><span style="font-size:10.5pt;font-family:Arial,sans-serif;color:rgb(65,65,65)"> </span></b><span style="font-family:"Times New Roman",serif;color:rgb(31,73,125)"><img border="0" width="254" height="116" style="width: 2.6458in; height: 1.2083in;" id="m_-7931993680594933061Picture_x0020_1" src="cid:ii_19243b396a04cff311" alt="signature_3970890138"></span><span style="font-size:11pt;font-family:Calibri,sans-serif;color:rgb(33,33,33)"><u></u><u></u></span></p>
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<p class="MsoNormal"><u></u> <u></u></p>
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</div></blockquote></div><br clear="all"><div><br></div><span class="gmail_signature_prefix">-- </span><br><div dir="ltr" class="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><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><div><br></div><div><a href="https://urldefense.us/v3/__http://www.cse.buffalo.edu/*knepley/__;fg!!G_uCfscf7eWS!bEvuhZjmSUukrYMa5jGF9VlNNxVETTLlIXH3aoOO8d6G9TdvzgX4lzosRefIY55K1fOFTKHxQQ4s_UJyPyvC$" target="_blank">https://www.cse.buffalo.edu/~knepley/</a><br></div></div></div></div></div></div></div></div>