Speed up to 4 processors should have at least 40,000 equations for 3D problems and more for 2D. 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.
Mark On Wed, Mar 15, 2023 at 9:09 PM 권승리 / 학생 / 항공우주공학과 <[email protected]> wrote: > Thank you for your reply. > > It was a simple problem, but it has more than 1000 degrees of freedom. > > Is this not enough to check speedup? > > Best regards > Seung Lee Kwon > > 2023년 3월 15일 (수) 오후 8:50, Matthew Knepley <[email protected]>님이 작성: > >> On Wed, Mar 15, 2023 at 3:38 AM 권승리 / 학생 / 항공우주공학과 <[email protected]> >> wrote: >> >>> Dear petsc developers. >>> >>> Hello. >>> I am trying to solve the structural problem with FEM and test parallel >>> computing works well. >>> >>> However, even if I change the number of cores, the total time is >>> calculated the same. >>> >>> I have tested on a simple problem using a MUMPS solver using: >>> mpiexec -n 1 >>> mpiexec -n 2 >>> mpiexec -n 4 >>> ... >>> >>> Could you give me some advice if you have experienced this problem? >>> >> >> If your problem is small, you could very well see no speedup: >> >> >> https://petsc.org/main/faq/#what-kind-of-parallel-computers-or-clusters-are-needed-to-use-petsc-or-why-do-i-get-little-speedup >> >> Thanks, >> >> Matt >> >> >>> Best regards >>> Seung Lee Kwon >>> -- >>> Seung Lee Kwon, Ph.D.Candidate >>> Aerospace Structures and Materials Laboratory >>> Department of Mechanical and Aerospace Engineering >>> Seoul National University >>> Building 300 Rm 503, Gwanak-ro 1, Gwanak-gu, Seoul, South Korea, 08826 >>> E-mail : [email protected] >>> Office : +82-2-880-7389 >>> C. P : +82-10-4695-1062 >>> >> >> >> -- >> What most experimenters take for granted before they begin their >> experiments is infinitely more interesting than any results to which their >> experiments lead. >> -- Norbert Wiener >> >> https://www.cse.buffalo.edu/~knepley/ >> <http://www.cse.buffalo.edu/~knepley/> >> > > > -- > Seung Lee Kwon, Ph.D.Candidate > Aerospace Structures and Materials Laboratory > Department of Mechanical and Aerospace Engineering > Seoul National University > Building 300 Rm 503, Gwanak-ro 1, Gwanak-gu, Seoul, South Korea, 08826 > E-mail : [email protected] > Office : +82-2-880-7389 > C. P : +82-10-4695-1062 >
