WRF on Azure amd64 arch

[Fima Rotter]

Hello!
I am trying to run WPS+WRF 4.5 on Azure VM instance with arm64 architecture (GNU compilers). Previously we had success with running on AWS arm64 instances, providing much better performance than the x64 arch.

However, with Azure instances we are getting cryptic failure without stack trace when running real.exe:

Full level index =   49     Height = 18702.9 m      Thickness =  592.3 m
Full level index =   50     Height = 19295.2 m      Thickness =  592.3 m
Full level index =   51     Height = 19887.5 m      Thickness =  592.3 m
calling inc/HALO_EM_VINTERP_UV_1_inline.inc
Segmentation fault (core dumped)

I cannot see the "core dumped" anywhere...

Did anyone had luck with Azure arm64?
Any help would be appreciated!

 

[kwerner]

Hi,
Apologies for the delay in response. If this case is able to run successfully on a different system, it probably has something to do with the specific Azure environment.

I also notice that you are providing a real.log file, and not an rsl.error.0000 file, which I assume means you have compiled WRF to run serially? If that's the case, then even if you are able to get past the real.exe issue, you will likely need parallel processing for the domain size you're using, since you'll probably need more than a single compiler. Take a look at Choosing an Appropriate Number of Processors for an explanation. I could be wrong, but I don't think that's what's causing your real.exe issue, as I think you should be able to run real.exe using a single processor for your domain, but you could first try to reinstall WRF using the dmpar option during configuration (you will need to make sure MPI is installed) and see if you're still getting the same issue. If so, then I would recommend reaching out to a support person at Azure to see if they are able to help.