Fix serial-MPI non-reproducibility for gswp3 CASA-CNP configuration#567
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Initialisation of CASA types was added in #590. Need to rebase. |
Currently the phen type is not initialised properly in the MPI implementation and results in uninitialised values being written to the restart file. This change initialises the phen type on allocation so it is initialised for both serial and MPI applications.
Some CASA variables required in the output file are not being communicated back to the master process from the workers. This change communicates the required variables from worker to master and is required to restore bitwise reproducibility in the CASA netcdf output file between serial and MPI runs.
Currently the MPI implementation does not output time-averaged pools and fluxes (#566). This change implements the time-averaging functionality which exists in the serial driver into the MPI master driver. This is required to restore bitwise reproducibility in the CASA netcdf output file across serial and MPI runs.
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Rebased off main. I've confirmed MPI and serial are still bitwise reproducible for CASA and CABLE outputs. @Whyborn do you mind giving this a review? |
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Looks good to me, and I get bit-wise compatibility now.
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Re-ran benchcab runs, all good 🙂 |
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Currently running serial and MPI runs for the gswp3 configuration (see MPI and serial configurations) with CASA-CNP enabled1 shows bitwise differences between serial and MPI runs in the CASA restart and CASA NetCDF output file (all other outputs, e.g. standard CABLE outputs and restarts, are bitwise identical between serial and MPI). This change fixes a few bugs in the MPI master driver and the CASA-CNP code so that we have bitwise reproducibility between serial and MPI in the CASA output and restart files for this configuration.
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📚 Documentation preview 📚: https://cable--567.org.readthedocs.build/en/567/
Footnotes
Note: CASA-CNP was enabled without a CASA restart file (i.e.
cable_user%CASA_fromZero = .TRUE.). ↩