ORCHIDEE performance (trunk revision 3623)

At this page the performances for ORCHIDEE in offline mode are detailed.
See here the performances for ORCHIDEE in the coupled model LMDZOR_v6 and IPSLCM6 : ​https://forge.ipsl.jussieu.fr/igcmg/wiki/PerformancesIPSLCM6

Orchidee scalability for different horizontal resolutions

Following table is based on tests with following set up:

• Simulation length: 1Y
• FG2.CWRR configuration:
  • HYDROL_CWRR = y, RIVER_ROUTING = y, STOMATE_OK_STOMATE = y, OK_EXPLICITSNOW = y, OK_FREEZE = n.
  • This is the standard set, read more here ReferenceSimulations
• Output level: monthly and daily output
• MPI parallelization
  • 1MPI is used for the server XIOS, the rest are used for Orchidee executable
  • no server is used for 1 MPI case or for the case with IOIPSL
• using the standard driver dim2_driver.f90

Conclusion

For the trunk ORCHIDEE it is recommended to use XIOS with 1 server. See in this table the recommended number of processes for a given resolution for global simulations with the corresponding CPU time for 10 years of simulation. The computing time is the same at curie and ada.

Forcing file resolution	Recommended number of processes	Real computing time / 10 years	Total computing time / 10 years
2 deg	31 MPI orchidee + 1 MPI XIOS server	43 m	22 h
1 deg	63 MPI orchidee + 1 MPI xios server	1 h 20m	85 h
0.5 deg	63 MPI orchidee + 1 MPI xios server	4 h	260 h

Note: The total(requested) computing time should be used in the demand for computing resources at TGCC and IDRIS.

The total cpu time is calculated by multiplying the real time with the numbers of MPI used.

Details

XIOS (using restart files)

Reference simulation

	1 MPI	4 MPI	8 MPI	16 MPI	32 MPI	64 MPI	128 MPI
twodeg	1h21	29m	13m45	7m06	4m24*	3m11	3m20
onedeg	Mem limit	1h40	47m03	23m	12m42	8m13*	7m05
halfdeg	Not tested	Mem limit	2h50	1h20	42m07	24m02*	20m36

*: Recommended number of processors

XIOS (start without restart files)

XIOS only writes the history outputs files.

	1 MPI	4 MPI	8 MPI	16 MPI	32 MPI	64 MPI	128 MPI
twodeg	1h25	32m18	17m1	10m23	7m33	6m12	6m30
onedeg	Not possible	Mem limit	57m	33m40	23m07	18m32	17m50
halfdeg	Not possible	Mem limit	3h33	2h03	1h25	1h05	1h02

IOIPSL (using restart files)

	1 MPI	4 MPI	8 MPI	16 MPI	32 MPI	64 MPI	128 MPI
twodeg	1h34	26m04	13m39	7m31	4m40	3m15	2m38
onedeg	5h56	1h34	52m57	28m54	17m30	12m	8m53
halfdeg	>16h40 (max limit)	6h23	3h50	2h08	1h17	50m34	36m45

IOIPSL (start without restart files)

Only IOIPSL enabled.

	1 MPI	4 MPI	8 MPI	16 MPI	32 MPI	64 MPI	128 MPI
twodeg	1h37	29m	16m36	10m20	7m30	5m59	5m21
onedeg	5h39	1h48	1h03	36m44	28m10	21m47	19m33
halfdeg	>16h40 (max limit)	7h21	4h32	2h49	1h58	1h32	1h17

Orchidee scalability to the output level - TODO -

In this table the set up FG2.CWRR is used with 63MPI for orchidee_ol and 1MPI for the server XIOS. For the case with IOIPSL, then 64MPI are used for orchidee_ol. The first line describes different levels of output.

	yearly with XIOS	monthly with XIOS	monthly and daily with XIOS	daily and 3hour with XIOS	daily and 3hour with IOIPSL
twodeg
onedeg
halfdeg