Enable parallell in windows

mark.meredith · August 18, 2020, 5:36pm

Yes, using Linux within a virtual machine such as VirtualBox or VMWare on Windows would works. Using WSL2 would also be possible. The performance for a laptop or desktop system in a virtual environment would likely be comparable to running Linux natively on the same hardware (I would guess.)

fmarchelli · February 18, 2021, 10:04am

Hi! I am doing a CFD-DEM simulation of a cylindrical liquid-solid fluidized bed. I have tried the method that @tyurata described and indeed it works, but only with the Hookean collision method. If I try to change it to Hertzian, the program computes one time step, and then it stops without giving any error. Does anybody know if this can be solved? Thanks!

cgw · February 18, 2021, 2:24pm

Hi Filippo - can you upload your project files, and we’ll have a look? You can use ‘Submit bug report’ to create a zip file containing everything.

Charles

fmarchelli · February 18, 2021, 2:52pm

Hi Charles, thanks for the reply. Here is the zip file.

Filippo

fb-mono_2021-02-18T154147.803473.zip (4.9 MB)

jeff.dietiker · February 18, 2021, 3:40pm

The files you sent work fine with me on Linux. What do you mean by the program “stops without giving any error”? It could be running but very slowly with the Hertzian model and a large Young’s modulus. It takes 36 seconds for the DEM loop to complete on my machine.

cgw · February 18, 2021, 3:47pm

Fails to build, for me

/tmp/fb-mono_2021-02-18T154147.803473/calc_collision_wall_mod.f:955:24:

  955 |                QSWALL = DES_CONDUCTION_WALL(OVERLAP,K_s0(phase_LL), &
      |                        1
Error: Type mismatch in argument ‘i’ at (1); passed REAL(8) to INTEGER(4)
gmake[2]: *** [CMakeFiles/udfs.dir/build.make:82: CMakeFiles/udfs.dir/tmp/fb-mono_2021-02-18T154147.803473/calc_collision_wall_mod.f.o] Error 1
gmake[1]: *** [CMakeFiles/Makefile2:174: CMakeFiles/udfs.dir/all] Error 2
gmake: *** [Makefile:149: all] Error 2
==============================================================
                      BUILD FAILED
==============================================================

That’s gfortran 10.2.0 on Linux. Trying Windows now.

jeff.dietiker · February 18, 2021, 4:11pm

This file is not compatible with the latest MFiX version. It works with 20.2.

cgw · February 18, 2021, 4:36pm

@fmarchelli
your file has

!MFIX-GUI OMP_NUM_THREADS = 16

OMP is not supported on Windows. The control in the run popup is disabled:
Capture

The “Threads” control is disabled but it’s set to 16. How did you get this set to 16?

I suggest removing that line from fb.mfx (edit the file carefully, while not running MFiX, then reload it). Will your job run without this setting?

OpenMP might work on Windows some day, but it’s not supported by us at this time, and would take some work to get going. If you can, run your parallel jobs on Linux!

Charles

fmarchelli · February 18, 2021, 5:35pm

Hi Jeff, thanks for the help, I really think it is stopping, please see this screenshot:

If I follow the exact same procedure but with the Hookean model instead, the simulation works just fine.

@cgw I am not using the GUI and, following the steps described in this thread, I can use 16 threads even on Windows. I understand that it is not supported and thus it may not work in all cases, I will try to run it on Linux. Thanks!