Fluids

Fluids

MPI issue when running Fluent 2021 R2 on supercomputer

    • Xicheng1
      Subscriber

      Hi everyone,


      I recently updated Fluent from 2019 R2 to 2021 R2 as the new supercomputer in our school only supports the latest version.

      I also update my case as it can be run by Fluent 2021 R2. I tried 10 cores parallelization in my local machine and it works perfectly. When I upload it to the supercomputer and run with 128 cores, it returns errors like these:

    • Rob
      Ansys Employee
      Staff are not permitted to open attachments, please re-post the log (if you need a couple of posts that's fine).
    • Xicheng1
      Subscriber
      Hi, Rob Thanks for your reply.
      The log file looks like below. I skip a section that just shows node information as the first figure.


    • Rob
      Ansys Employee
      Try on around half the number of cores. The error is system side, but could be a number of causes. File corruption is one possible, then we're into network hiccups and more IT related issues.
    • Xicheng1
      Subscriber
      Thanks, Robs Yes, I tried to use 64 cores and it returns the same error.
      The file is fine when I run it on my local machine using the same command, it works perfectly.
      I also forward this issue to the staff of the supercomputer team and wait for their reply.


    • Rob
      Ansys Employee
      Not sure then. Looking in more detail 800k cells won't scale all that well beyond 8-16 cores depending on physics as the data transfer cost can outweigh benefit of the extra cores.
Viewing 5 reply threads
  • You must be logged in to reply to this topic.