<div dir="ltr"><div dir="ltr"><br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, Dec 6, 2021 at 5:59 PM Matthew Knepley <<a href="mailto:knepley@gmail.com">knepley@gmail.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div dir="ltr">On Mon, Dec 6, 2021 at 7:54 PM Fande Kong <<a href="mailto:fdkong.jd@gmail.com" target="_blank">fdkong.jd@gmail.com</a>> wrote:<br></div><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div dir="ltr">Thanks, Matt,<div><br></div><div>Sorry, I still have more questions on this example. How to refine mesh to make the problem larger? </div><div><br></div><div>I tried the following options, and none of them worked. I might do something wrong.</div><div><br></div><div>-ex56_dm_refine 9<br></div><div><br></div><div>and </div><div><br></div><div>-dm_refine 4</div></div></blockquote><div><br></div><div>The mesh handling in this example does not conform to the others, but it appears that</div><div><br></div><div> -ex56_dm_refine <k></div><div><br></div><div>should take effect at</div><div><br></div><div> <a href="https://gitlab.com/petsc/petsc/-/blob/main/src/snes/tutorials/ex56.c#L381" target="_blank">https://gitlab.com/petsc/petsc/-/blob/main/src/snes/tutorials/ex56.c#L381</a></div><div><br></div></div></div></blockquote><div><br></div><div>I was puzzled about this because DMSetFromOptions does not seem to trigger -ex56_dm_refine.</div><div><br></div><div>I did a search, and could not find where we call "<span class="gmail-Apple-converted-space"> </span>-ex56_dm_refine" in PETSc. </div><div><br></div><div>I got the same result by running the following two combinations:</div><div><br></div><div>1) ./ex56 -log_view -snes_view -max_conv_its 3 -ex56_dm_refine 10<br><br>2) ./ex56 -log_view -snes_view -max_conv_its 3 -ex56_dm_refine 0<br></div><div><br></div><div>Thanks,</div><div><br></div><div>Fande</div><div><br></div><div><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div class="gmail_quote"><div></div><div>unless you are setting max_conv_its to 0 somehow.</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-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div>Thanks,</div><div><br></div><div>Fande</div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, Dec 6, 2021 at 5:04 PM Matthew Knepley <<a href="mailto:knepley@gmail.com" target="_blank">knepley@gmail.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div dir="ltr">On Mon, Dec 6, 2021 at 7:02 PM Fande Kong <<a href="mailto:fdkong.jd@gmail.com" target="_blank">fdkong.jd@gmail.com</a>> wrote:<br></div><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div>Thanks, Matt</div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, Dec 6, 2021 at 4:47 PM Matthew Knepley <<a href="mailto:knepley@gmail.com" target="_blank">knepley@gmail.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div dir="ltr">On Mon, Dec 6, 2021 at 6:40 PM Fande Kong <<a href="mailto:fdkong.jd@gmail.com" target="_blank">fdkong.jd@gmail.com</a>> wrote:<br></div><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div dir="ltr">Dear PETSc team,<div><br><div>I am interested in a careful evaluation of PETSc GPU performance in our INL cluster. </div><div><br></div><div>Any example in PETSc that can show GPU speedup with solving a nonlinear equation? </div><div><br></div><div>I talked to Junchao; he suggested that I try SNES/tutorial/ex56. I tried that, but I could not find any speedup using the GPU. I could attach some results of "log_view" later if we would like to see that. </div></div></div></blockquote><div><br></div><div>We should note that you will only see speedup in the solver, so that problem has to be pretty large. I believe Mark has good results with it.</div><div>The assembly is still all on the CPU. I am working on this over break, and hope to have a CEED version of it by the new year.</div></div></div></blockquote><div><br></div><div>Are both function and matrix assmelies on CPU? Or just the matrix assembly?</div></div></div></blockquote><div><br></div><div>There is no GPU assembly right now.</div><div><br></div><div> Matt</div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div class="gmail_quote"><div>OK, I will try to check the solver part </div><div><br></div><div>Thanks, again </div><div><br></div><div>Fande </div><div><br></div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div class="gmail_quote"><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-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div><div>Appreciate any instructions/comments about running a simple PETSc GPU example to get a speedup. </div><div><br></div><div>Thanks,</div><div><br></div><div>Fande</div></div></div>
</blockquote></div><br clear="all"><div><br></div>-- <br><div dir="ltr"><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="http://www.cse.buffalo.edu/~knepley/" target="_blank">https://www.cse.buffalo.edu/~knepley/</a><br></div></div></div></div></div></div></div></div>
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</blockquote></div><br clear="all"><div><br></div>-- <br><div dir="ltr"><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="http://www.cse.buffalo.edu/~knepley/" target="_blank">https://www.cse.buffalo.edu/~knepley/</a><br></div></div></div></div></div></div></div></div>
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</blockquote></div><br clear="all"><div><br></div>-- <br><div dir="ltr"><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="http://www.cse.buffalo.edu/~knepley/" target="_blank">https://www.cse.buffalo.edu/~knepley/</a><br></div></div></div></div></div></div></div></div>
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