<div dir="ltr">Speed up to 4 processors should have at least 40,000 equations for 3D problems and more for 2D.<div>At least for iterative solvers. This is probably a good place to start with direct solvers but you might see benefit with a little less.<br><div><br></div><div>Mark</div></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Wed, Mar 15, 2023 at 9:09 PM 권승리 / 학생 / 항공우주공학과 <<a href="mailto:ksl7912@snu.ac.kr">ksl7912@snu.ac.kr</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr">Thank you for your reply.<div><br></div><div>It was a simple problem, but it has more than 1000 degrees of freedom.</div><div><br></div><div>Is this not enough to check speedup?</div><div><br></div><div><div>Best regards</div><div>Seung Lee Kwon</div></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">2023년 3월 15일 (수) 오후 8:50, Matthew Knepley <<a href="mailto:knepley@gmail.com" target="_blank">knepley@gmail.com</a>>님이 작성:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div dir="ltr">On Wed, Mar 15, 2023 at 3:38 AM 권승리 / 학생 / 항공우주공학과 <<a href="mailto:ksl7912@snu.ac.kr" target="_blank">ksl7912@snu.ac.kr</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 dir="ltr">Dear petsc developers.<div><br></div><div>Hello.</div><div>I am trying to solve the structural problem with FEM and test parallel computing works well.</div><div><br></div><div>However, even if I change the number of cores, the total time is calculated the same.</div><div><br></div><div>I have tested on a simple problem using a MUMPS solver using:</div><div>mpiexec -n 1</div><div>mpiexec -n 2</div><div>mpiexec -n 4<br></div><div>...</div><div><br></div><div>Could you give me some advice if you have experienced this problem?</div></div></blockquote><div><br></div><div>If your problem is small, you could very well see no speedup:</div><div><br></div><div> <a href="https://petsc.org/main/faq/#what-kind-of-parallel-computers-or-clusters-are-needed-to-use-petsc-or-why-do-i-get-little-speedup" target="_blank">https://petsc.org/main/faq/#what-kind-of-parallel-computers-or-clusters-are-needed-to-use-petsc-or-why-do-i-get-little-speedup</a></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 dir="ltr"><div><div><div>Best regards</div><div>Seung Lee Kwon<br></div></div><span>-- </span><br><div dir="ltr"><div dir="ltr"><div>Seung Lee Kwon, Ph.D.Candidate</div><div>Aerospace Structures and Materials Laboratory</div><div>Department of Mechanical and Aerospace Engineering</div><div>Seoul National University</div><div>Building 300 Rm 503, Gwanak-ro 1, Gwanak-gu, Seoul, South Korea, 08826</div><div>E-mail : <a href="mailto:ksl7912@snu.ac.kr" target="_blank">ksl7912@snu.ac.kr</a></div><div>Office : +82-2-880-7389</div><div>C. P : +82-10-4695-1062</div></div></div></div></div>
</blockquote></div><br clear="all"><div><br></div><span>-- </span><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>
</blockquote></div><br clear="all"><div><br></div><span>-- </span><br><div dir="ltr"><div dir="ltr"><div>Seung Lee Kwon, Ph.D.Candidate</div><div>Aerospace Structures and Materials Laboratory</div><div>Department of Mechanical and Aerospace Engineering</div><div>Seoul National University</div><div>Building 300 Rm 503, Gwanak-ro 1, Gwanak-gu, Seoul, South Korea, 08826</div><div>E-mail : <a href="mailto:ksl7912@snu.ac.kr" target="_blank">ksl7912@snu.ac.kr</a></div><div>Office : +82-2-880-7389</div><div>C. P : +82-10-4695-1062</div></div></div>
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