coupling issue of main calculation never started

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ywan459
Posts: 20
Joined: Thu Nov 25, 2021 9:13 pm

coupling issue of main calculation never started

Post by ywan459 »

Hi developers and users,

I have issue to run the coupling problem from the tutorial. I have installed code_saturne 7.0 and syrthes 5.0, The individual tests of solid and fluids part were fine. Once all coupled the solution procedure stopped at just after "main calculation" showed in the run_log. Syrthes listing file showed "segmentation fault". I guess this might due to setup issue.

I have attached the key log files here. I am wondering whether this is case setup issue or the installation issue. and How do I fix it. Thank you very much!

Regards
ywan459
Attachments
preprocessor.log
(5.95 KiB) Downloaded 98 times
performance.log
(1.49 KiB) Downloaded 85 times
compile.log
(4.38 KiB) Downloaded 94 times
ywan459
Posts: 20
Joined: Thu Nov 25, 2021 9:13 pm

Re: coupling issue of main calculation never started

Post by ywan459 »

Here are more log files
Attachments
setup.log
(28.08 KiB) Downloaded 82 times
run_solver.log
(22.65 KiB) Downloaded 85 times
ywan459
Posts: 20
Joined: Thu Nov 25, 2021 9:13 pm

Re: coupling issue of main calculation never started

Post by ywan459 »

More log files from Syrthes side (Solid part).
Attachments
listing.txt
(10.62 KiB) Downloaded 85 times
compile.log
(1.03 KiB) Downloaded 87 times
Yvan Fournier
Posts: 4070
Joined: Mon Feb 20, 2012 3:25 pm

Re: coupling issue of main calculation never started

Post by Yvan Fournier »

Hello,

The logs show a crash on the Sythes side.

If you can run Syrthes under a debugger, even with a non-debug build of Syrthes, you could at least know where it crashed. If you do not know how to do this, I can point you to some documentation, and code_saturne has a standalone debug wrapper script (in bin/cs_debug_wrapper.py in the code's sources) which can help.

Also, unless you mesh is too big, I would recommend starting with only 1 MPI process for Syrthes. You also seem to be using OpenMP on the code_saturne side. I do not believe Syrthes has OpenMP support, so unless you modify the mpiexec command in the case's generated "run_solver" script to make it smarter, you will be wasting resources in the Syrthes side, Using pure MPI (with more MPI ranks on the code_saturne side) is probably better.

Also remember that with code_saturne v7.0, unless you need some specific features of Syrthes (contact resistance, transparent radiative model), you can try code_saturne's internal coupling instead.

Best regards,

Yvan
ywan459
Posts: 20
Joined: Thu Nov 25, 2021 9:13 pm

Re: coupling issue of main calculation never started

Post by ywan459 »

Hi Yvan,

Thanks for your valuable feedback! Yes, you are very right, I am using openMPI for both code_saturne and syrthes. I have complied both, and tested the multi-process cases (from the testing examples). Both results showed no problem at all.

I will purge the openMP and compile CS and syrthes with MPICH as the first step of trail-error debug. Actually I am also planning of testing the internal coupling as well.

Will update......

Regards
ywan459
ywan459
Posts: 20
Joined: Thu Nov 25, 2021 9:13 pm

Re: coupling issue of main calculation never started

Post by ywan459 »

Hi Yvan,

I have removed the openMPI and complied the CS and Syrthes with MPICH. Both solvers were tested and successfully produced the test cases results. The coupling case was crashed due to the same problem - segmentation fault. You may see the messages on the attached files.

I am wondering of how to activate the debug mode. Could you please show me the docs? Thank you very much!

Regards
ywan459
Attachments
run_solver.log
(21.02 KiB) Downloaded 86 times
listing.txt
(6.48 KiB) Downloaded 86 times
summary.txt
(5.96 KiB) Downloaded 84 times
Yvan Fournier
Posts: 4070
Joined: Mon Feb 20, 2012 3:25 pm

Re: coupling issue of main calculation never started

Post by Yvan Fournier »

Hello,

Regarding the launch under a debugger, you can check the GUI, under "Run Computation./AdvancedTool Options" and click on the help box to see how to to add a debugger. This will only do so for the code_saturne part, but you can then go to the RESU/<run_id> directory, and adapt the "run_solver" script to call the debugger for Syrthes instead.

There is an updated Doxygen page regarding debugging, that will appear when we release 7.1 (before the end of the month). It will not be on the web site until v7.1, but if you download/install the master branch from Git, and generate a local Doxygen documentation ("make html"), you can get a local install of that.

Best regards,

Yvan
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