Elmer Discussion Forum

kevinarden wrote: ↑16 Jun 2021, 17:54 Do you run ElmerSolver for the GUI or a command line in general from a command line

You must first partition mesh to number of processors for example 4

ElmerGrid 2 2 Mymeshname -partdual -metiskway 4

then execute the mpi solver of the machine if it is openmpi then likely

mpirun -np 4 ElmerSolver_mpi

assuming the case.sif file is in the ELMERSOLER_STARTINFO file if not than

mpirun -np 4 ElmerSolver_mpi mycase.sif


If running from ElmerGUI go to run parallel settings and check parallel solver set number of processes, then set the commands in the window.

raback wrote: ↑16 Jun 2021, 22:01 Hi

Usually sif file stays the same. There may be some features that do not work out of the box. It is good idea to verify that you get the same results in serial and parallel by comparing the results.

How many real cores do you have on your machine?

-Peter

kevinarden wrote: ↑17 Jun 2021, 12:01 You go to run, parallel setting, check the box on hot select number of processes.
You will likely have to find the name of the mpi exectuable on the system, you can try the default, but it is probably different.

kevinarden wrote: ↑17 Jun 2021, 12:56 Good news is that the mesh partition with ElmerGrid work

Problem is that last line in the output

Unable to start parallel solver

means that you do not have the right mpi executable name in executable field, either you have a different mpi solver installed on the system or there is no mpi solver on the system.