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real (and wrf) "crashing" if more than 4 cores used (Intel compiler, dmpar)

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I couldn't find a better title for this topic for the following. If I try to use more than 4 cores real.exe does not start (no rsl log files) and the terminal crashes! If I set exactly 4 cores for real and more than 4 cores for wrf.exe, then the same problem happens for wrf.exe. If I set exactly 4 cores for both, than real and wrf running ok.

I have a Linux machine (kernel 5.12.8-300.fc34.x86_64) on AMD Ryzen 9 5900X 12-Core Processor. I built everything by last Intel compile (icc/ifort) using dmpar configuration and mpich-3.4.2.

Pay attention: compiling and using smpar it is ok. Compiling by GNU compiler both dmpar than smpar are ok.

i don't know what to do because I would like to use dmpar (intel) for more than 4 cores!

Thanks for your support, any suggestions are welcome.

PS: trying the same thing on another computer, which has the same linux kernel, but intel instead of amd processor, this "strange problem" doesn't happen ...
I am suspicious this is a machine issue. I talked to our software engineer and we believe this might be a 'trick' related to AMD processor. Unfortunately we cannot provide a solution since we cannot repeat this problem. Please keep us updated if you eventually know for sure what is going on. Someone else in the community may have the same issue....
Thanks for the answer, also in my opinion the problem is related to the processor. I have also written to the intel community, if I have answers I will not fail to report them here.