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Parallel computation is failing to start (that's all the log says)

Posted: 16 Jan 2024, 00:10
by ender_wiggin
I'm trying to simulate a radiative heat transfer + linear elasticity model with a mesh I built in Salome. The log file simply says the parallel solver failed to start.

I'm using the Windows GUI+MPI binary compiled shortly before December 23, 2023. I have previously used the parallel solver with success.

I have attached the sif and log files.

I'm not sure what else to say because I cannot find any errors being printed out in the log.

Re: Parallel computation is failing to start (that's all the log says)

Posted: 16 Jan 2024, 17:31
by Rich_B
Hello,

It would help if you would post the command line entries that you used. A working example would be even more helpful. Elmer is very flexible, which also means lot's of little things can go wrong. If your model isn't proprietary, maybe you could post it on a file sharing location, such as github.

Rich.

Re: Parallel computation is failing to start (that's all the log says)

Posted: 16 Jan 2024, 18:27
by ender_wiggin
I will see what I can do for posting a model.

Also, unless I should put all things done through the GUI on the ElmerGUI forum regardless of the situation, I deemed that this is generally unrelated to the GUI itself as opposed to an issue with how the solver is launched. I can certainly provide a screenshot of the parallel computation dialogue box which, as far as I know, provides the information for exactly how parallel solutions are launched.

Re: Parallel computation is failing to start (that's all the log says)

Posted: 16 Jan 2024, 19:21
by Rich_B
Hello,

A screenshot will help. Being able to duplicate your run is very helpful.

Rich.

Re: Parallel computation is failing to start (that's all the log says)

Posted: 16 Jan 2024, 23:20
by raback
Hi,

I would recommend always starting any given problemtype in serial and only going parallel (and up-scaling) only when a reasonable solution has been established. This is pretty basic so there should be no major caveats but obviously it does not find the parallel solver.

-Peter

Re: Parallel computation is failing to start (that's all the log says)

Posted: 17 Jan 2024, 16:30
by Rich_B
Hello,

I was able to duplicate the error. . All I did was take a working ElmerGUI parallel example, open parallel settings, and in the 'Executable' box, misspell 'mpiexec.exe', and then run.
Unable to start parallel solver
Rich.

Re: Parallel computation is failing to start (that's all the log says)

Posted: 17 Jan 2024, 19:16
by kevinarden
That would certainly break it, another other would be not having the path to ElmerSolver defined, a third would not be having mpi installed, or having the other mpi installed that uses a different executable then mpiexec.exe (microsoft versus openmpi)

Re: Parallel computation is failing to start (that's all the log says)

Posted: 17 Jan 2024, 21:02
by Rich_B
Using the same parallel ElmerGUI example, and mis-spelling 'ElmerSolver', gives this error message:
ERROR: Error reported: failed to launch 'ElmerSolv0er_mpi.exe' on DESKTOP-D6N8F4T
Error (2) The system cannot find the file specified.
Another case, with ElmerSolver spelled properly and adding an invalid option '-nvist', gives this error message:
Unknown option: -nvist
Rich.

Re: Parallel computation is failing to start (that's all the log says)

Posted: 17 Jan 2024, 21:03
by kevinarden
I test my system by repeating what is in the ElmerGUI set up in a command window, that way you get OS errors, not Elmer's report of couldn't start the solver
command.png
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