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Segmentation fault

This post was from a previous version of the WRF&MPAS-A Support Forum. New replies have been disabled and if you have follow up questions related to this post, then please start a new thread from the forum home page.


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I am trying to change from a 1km to 5 km grid to reduce the computational resources needed to run my model. I have changed dx and dy values in namelist.wps and namelist.input. I re run geogrid.exe and metgrid.exe. These work fine I then move over to WRFV3/run and link my output files. I then attempt to run real.exe. It does not work. I get a segmentation fault. What am I doing wrong?

Can you upload your namelist.input file, as well as all of your rsl.error.* files (assuming you're running a dmpar-build case)? Just package all the files together in one .tar.gz file. If it's too large to upload on the forum, then you can upload here:

Just let me know when it's there and the name of the file, so that I can look for it.

Hi there,

I have uploaded the two files. I am not even sure where to start looking for the issue. Please let me know if there is anything I can clarify.

Note: I added a .txt extension to each file since the forum wouldn't allow me to upload the rsl file. I said it had an invalid extension.

Thank you very much,


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I'm a bit confused because you mention in the original post that you were getting the segmentation fault when running real.exe, but the rsl.error* file you uploaded is for wrf.exe. You also mention that you are modifying your namelist to change from a 1km resolution run, to a 5km resolution run, but the namelist you uploaded is a 1km run. Can you clarify which is correct with both of these concerns? If you uploaded the wrong namelist, can you send the one you are using that gives the segmentation fault? Can you also please upload all of the rsl.error* files (as I mentioned before, you can package those together in a *.tar file)?

Sorry about that. I also realized this thread is posted in the wrong folder :(

I do get the segmentation fault when running wrf.exe. I have tried running a reduced number of processors. I also was wondering if perhaps my input meteorological data didn't align with my geographical data. I got some new meteorological data and tried running with that. I still got the segmentation error when in module SFCLAY.

I have attached the rsl.error.0000 file along with my namelist.input and namelist.wps files. I also included the sfclay.f file (I don't know that this is helpful).

To clarify I am using a 1km grid and the issue occurs when I run wrf.exe. real.exe finishes its run succcessfully. Also I reduced the number of processors I used to run the code so there is only one rsl.error file.


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Okay I think I finally tracked down the problem. It is with the variable you have set in the &dynamics section of your namelist: pert_coriolis = .true.
This is something that is used for LES simulations (DX ~100m), but you are running a 1km resolution simulation, so it shouldn't be set to true for this application. Try removing that and see if that makes a difference.