[petsc-users] Question about time issues in parallel computing

[­권승리 / 학생 / 항공우주공학과]

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 <knepley at gmail.com>님이 작성:

> On Wed, Mar 15, 2023 at 3:38 AM ­권승리 / 학생 / 항공우주공학과 <ksl7912 at snu.ac.kr>
> 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 : ksl7912 at snu.ac.kr
>> 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 : ksl7912 at snu.ac.kr
Office : +82-2-880-7389
C. P : +82-10-4695-1062
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