Now that you have compiled the MITgcm and copied the executable to the run directory, you can start a MITgcm simulation. We will look at the file
Run scripts
In the global_hg_llc90/run, pfos/run, and pcb/run directory, you will find everal sample scripts that you can use to run MITgcm jobs.
| Simulation type | Run script | data.exch file | data file |
|---|---|---|---|
| 13 CPUs, debug run (10 hours) | run.mitgcm.13np.debug | data.exch2.13np | data.debug.run |
| 13 CPUs, 1-month run | run.mitgcm.13np.1month | data.exch2.13np | data.1month_run |
| 96 CPUs, debug run (10 hours) | run.mitgcm.96np.debug | data.exch2.96np | data.debug_run |
| 96 CPUs, 20 year run | run.mitgcm.96np.20yr | data.exch2.96np | data.20yr_run |
We will look at each of these scripts in more detail below.
The run.mitgcm scripts
The run.mitgcm* scripts are used to start a MITgcm simulation with 13 CPUs (for debugging) or 96 CPUs. Each run script also copies the following files before starting the run
data.exch2.13np or data.exch2.96np ---> data.exch2
data.debug_run or data.1month_run or data.20yr_run ---> data
The data.exch2.13np and data.exch2.96np files
The data.exch2.13np contains the following namelist data declaration. This is used to set up the horizontal grid for 13 CPus.
&W2_EXCH2_PARM01 W2_printMsg = 0 , W2_mapIO = 1 , preDefTopol = 0 , #============================================================================== #-- 5 facets llc_120 topology (drop facet 6 and its connection): #============================================================================== dimsFacets(1:10) = 90, 270, 90, 270, 90, 90, 270, 90, 270, 90 , facetEdgeLink(1:4,1) = 3.4, 0. , 2.4, 5.1 , facetEdgeLink(1:4,2) = 3.2, 0. , 4.2, 1.3 , facetEdgeLink(1:4,3) = 5.4, 2.1, 4.4, 1.1 , facetEdgeLink(1:4,4) = 5.2, 2.3, 0. , 3.3 , facetEdgeLink(1:4,5) = 1.4, 4.1, 0. , 3.1 , /
The data,exch2.96np is used to set up the horizontal grid for 96 CPUs. It contains the same namelist variables as does data.exch2.13np, with an additional variable named blanklist. This is used to set certain tiles to zero.
&W2_EXCH2_PARM01
W2_printMsg = 0 ,
W2_mapIO = 1 ,
preDefTopol = 0 ,
#==============================================================================
#-- 5 facets llc_120 topology (drop facet 6 and its connection):
#==============================================================================
dimsFacets(1:10) = 90, 270, 90, 270, 90, 90, 270, 90, 270, 90 ,
facetEdgeLink(1:4,1) = 3.4, 0. , 2.4, 5.1 ,
facetEdgeLink(1:4,2) = 3.2, 0. , 4.2, 1.3 ,
facetEdgeLink(1:4,3) = 5.4, 2.1, 4.4, 1.1 ,
facetEdgeLink(1:4,4) = 5.2, 2.3, 0. , 3.3 ,
facetEdgeLink(1:4,5) = 1.4, 4.1, 0. , 3.1 ,
#==============================================================================
#-- 30x30 nprocs = 96 : Blank out certain tiles
#==============================================================================
blankList(1:21) = 1,2,3,5,6,28,29,30,31,32,33,49,50
52,53,72,81,90,99,108,117
/
The run.mitgcm* scripts will copy data.exch2.13np or data.exch2.96np to a file named data.exch2, so that you won't forget to do this yourself.
Debug run
Hello
1-month run
Hello
20 year run
Hello