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WRF ./real.exe problem for 10 year data (SIGSEGV: 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.


Dear WRF community,

I am writing for a ./real compilation problem for WRF V4.0. It has been successfully run for one whole year. And when I tried to process 10 years (2008-2017), there is an SIGSEGV error after typing ./real.exe.

It prompted out errors after processing half a year data (until 2008-09-06_06:00:00) as follows:

Program received signal SIGSEGV: Segmentation fault - invalid memory reference.

It seems to be a memory limit problem. Is there a file volumn limit for WRF ./real.exe?

The namelist.input and log.real files are attached. Any indications are appreciated. Thanks.


  • real.log
    1.8 MB · Views: 55
  • namelist.input
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To run real for this long of a period, you likely need to run it in increments, possibly for 2 reasons: 1) if you're using a batch queueing system, there are likely limitations to the number of hours you can run, and you will reach that limit before the run is completed. 2) There is a file size limit (4GB when large-file support is compiled - which is default since V3.9, so yours should be using it). The wrfinput/wrfbdy files are likely reaching that limit and then stopping the run. I would recommend running this for a couple of months at a time, and perhaps including a bit of overlap so that when you run wrf and restart the model, you can make sure to have boundary conditions for the time of your restart file. I'm sure you already were planning to, but when running wrf for this long, you will need to run with restarts - running for a period of time, and outputting restart files at certain intervals (not too often, as the model slows down when writing out files, but often enough so that if your run stops for any reason, you can restart from a file you have and won't lose too much data/time). You will also need to use the bucket options, which you can read about here:

If you run real.exe in increments as I've suggested, and are still getting a segmentation fault at the exact same time as before, then there is likely something going on with your input data.

Thanks Kelly, I tried to batch process ./real.exe for several months~years, and this method works.
--I tried to compare the period ./real.exe works (without restart), and found it can vary from ~9 months (2008,2009), to 2-3 years (2011-2014, 2014-2016), and then it stop.
--I do not know the exact reason causing the stop, but nearly sure there is no problem with input met_em* files (through setting different periods over the previous stop time point, and it works).

When adding bucket_mm=100 and bucket_J=1.e9 to namelist.input, ./wrf.exe would give an error for the first file as follows:
Program received signal SIGSEGV: Segmentation fault - invalid memory reference.
--When I change these two lines to: bucket_mm=-1 and bucket_J=-1, ./wrf.exe works successfully.

Is there anything more to pay attention in namelist.input? Wrf.log and namelist.input are attached. Thanks.


  • namelist.input.2019.04.01.txt
    4.4 KB · Views: 59
  • wrf.log.2019.04.01.txt
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Your new question seems to be a duplicate to this post:

As it's somewhat of a new topic, I have answered there. I'm glad you were able to get past your initial problem.