How to make a parallel run for nemo v3_3

Add a cpp key and compile

see list of keys for nemo v3_3

​http://www.nemo-ocean.eu/Using-NEMO/User-Guides/Basics/CPP-keys-V3_3

• Add key key_mpp_mpi and set number of processors in ORCA2_LIM/cpp_ORCA2_LIM.fcm, and compile:
  

  ./makenemo -m SX8_BRODIE -n ORCA2_LIM add_key "key_mpp_mpi nproci=2 nprocj=2"
  

Configure config.card

• Set same number of processors at compiling time in modipsl/config/ORCA2_LIM/IGCM00/config.card: :
  

  #-- Total Number of Processors 
  JobNumProcTot=#proc at compiling time
  

• Set a frequency for offline rebuild compatible with PeriodLength?

  RebuildFrequency=1Y
  

On brodie

• Enable multi NQS class :

  #-- PBS Class (required on brodie mono/multi)
  JobClass=multi
  

• Enable run multi processors option in modipsl/config/ORCA2_LIM/IGCM00/config.card: :
  

  #-- Run Options :
  JobRunOptions='"-np "${BATCH_NUM_PROC_TOT}"'
  

On vargas

• Change MPI send type in namelist

     cn_mpi_send =  'I'      !  mpi send/recieve type   ='S', 'B', or 'I' for standard send,
  

Tests

computer	date	config modipsl	config NEMO	Revision|	jpnij (jpnixjpnj)	length of simulation	Real Time for 1 year	dods link	name
vargas	15/10/09	NEMO_IGCM	ORCA2_LIM	1661	16	2Y/1Y	1000 s	​CLIMV16	M.-A. Foujols
brodie	15/10/09	NEMO_IGCM	ORCA2_LIM	1661	4	2Y/1Y	470 s	​CLIMB4	M.-A. Foujols
mercure	16/10/09	NEMO_IGCM	ORCA2_LIM	1670	4(1x4)	10Y/1Y	470 s	​v32bclim	S. Flavoni