eesupp/inc/CPP_EEOPTIONS.h

C $Header: /u/gcmpack/MITgcm/eesupp/inc/CPP_EEOPTIONS.h,v 1.42 2017/08/09 15:18:49 mlosch Exp $
C $Name:  $

CBOP
C     !ROUTINE: CPP_EEOPTIONS.h
C     !INTERFACE:
C     include "CPP_EEOPTIONS.h"
C
C     !DESCRIPTION:
C     *==========================================================*
C     | CPP\_EEOPTIONS.h                                         |
C     *==========================================================*
C     | C preprocessor "execution environment" supporting        |
C     | flags. Use this file to set flags controlling the        |
C     | execution environment in which a model runs - as opposed |
C     | to the dynamical problem the model solves.               |
C     | Note: Many options are implemented with both compile time|
C     |       and run-time switches. This allows options to be   |
C     |       removed altogether, made optional at run-time or   |
C     |       to be permanently enabled. This convention helps   |
C     |       with the data-dependence analysis performed by the |
C     |       adjoint model compiler. This data dependency       |
C     |       analysis can be upset by runtime switches that it  |
C     |       is unable to recoginise as being fixed for the     |
C     |       duration of an integration.                        |
C     |       A reasonable way to use these flags is to          |
C     |       set all options as selectable at runtime but then  |
C     |       once an experimental configuration has been        |
C     |       identified, rebuild the code with the appropriate  |
C     |       options set at compile time.                       |
C     *==========================================================*
CEOP

#ifndef _CPP_EEOPTIONS_H_
#define _CPP_EEOPTIONS_H_

C     In general the following convention applies:
C     ALLOW  - indicates an feature will be included but it may
C     CAN      have a run-time flag to allow it to be switched
C              on and off.
C              If ALLOW or CAN directives are "undef'd" this generally
C              means that the feature will not be available i.e. it
C              will not be included in the compiled code and so no
C              run-time option to use the feature will be available.
C
C     ALWAYS - indicates the choice will be fixed at compile time
C              so no run-time option will be present

C=== Macro related options ===
C--   Control storage of floating point operands
C     On many systems it improves performance only to use
C     8-byte precision for time stepped variables.
C     Constant in time terms ( geometric factors etc.. )
C     can use 4-byte precision, reducing memory utilisation and
C     boosting performance because of a smaller working set size.
C     However, on vector CRAY systems this degrades performance.
C     Enable to switch REAL4_IS_SLOW from genmake2 (with LET_RS_BE_REAL4):
#ifdef LET_RS_BE_REAL4
#undef REAL4_IS_SLOW
#else /* LET_RS_BE_REAL4 */
#define REAL4_IS_SLOW
#endif /* LET_RS_BE_REAL4 */

C--   Control use of "double" precision constants.
C     Use D0 where it means REAL*8 but not where it means REAL*16
#define D0 d0

C--   Enable some old macro conventions for backward compatibility
#undef USE_OLD_MACROS_R4R8toRSRL

C=== IO related options ===
C--   Flag used to indicate whether Fortran formatted write
C     and read are threadsafe. On SGI the routines can be thread
C     safe, on Sun it is not possible - if you are unsure then
C     undef this option.
#undef FMTFTN_IO_THREAD_SAFE

C--   Flag used to indicate whether Binary write to Local file (i.e.,
C     a different file for each tile) and read are thread-safe.
#undef LOCBIN_IO_THREAD_SAFE

C--   Flag to turn off the writing of error message to ioUnit zero
#undef DISABLE_WRITE_TO_UNIT_ZERO

C--   Alternative formulation of BYTESWAP, faster than
C     compiler flag -byteswapio on the Altix.
#undef FAST_BYTESWAP

C--   Flag to turn on old default of opening scratch files with the
C     STATUS='SCRATCH' option. This method, while perfectly FORTRAN-standard,
C     caused filename conflicts on some multi-node/multi-processor platforms
C     in the past and has been replace by something (hopefully) more robust.
#undef USE_FORTRAN_SCRATCH_FILES

C--   Flag defined for eeboot_minimal.F, eeset_parms.F and open_copy_data_file.F
C     to write STDOUT, STDERR and scratch files from process 0 only.
C WARNING: to use only when absolutely confident that the setup is working
C     since any message (error/warning/print) from any proc <> 0 will be lost.
#undef SINGLE_DISK_IO

C=== MPI, EXCH and GLOBAL_SUM related options ===
C--   Flag turns off MPI_SEND ready_to_receive polling in the
C     gather_* subroutines to speed up integrations.
#undef DISABLE_MPI_READY_TO_RECEIVE

C--   Control MPI based parallel processing
CXXX We no longer select the use of MPI via this file (CPP_EEOPTIONS.h)
CXXX To use MPI, use an appropriate genmake2 options file or use
CXXX genmake2 -mpi .
CXXX #undef  ALLOW_USE_MPI

C--   Control use of communication that might overlap computation.
C     Under MPI selects/deselects "non-blocking" sends and receives.
#define ALLOW_ASYNC_COMMUNICATION
#undef  ALLOW_ASYNC_COMMUNICATION
#undef  ALWAYS_USE_ASYNC_COMMUNICATION
C--   Control use of communication that is atomic to computation.
C     Under MPI selects/deselects "blocking" sends and receives.
#define ALLOW_SYNC_COMMUNICATION
#undef  ALWAYS_USE_SYNC_COMMUNICATION

C--   Control XY periodicity in processor to grid mappings
C     Note: Model code does not need to know whether a domain is
C           periodic because it has overlap regions for every box.
C           Model assume that these values have been
C           filled in some way.
#undef  ALWAYS_PREVENT_X_PERIODICITY
#undef  ALWAYS_PREVENT_Y_PERIODICITY
#define CAN_PREVENT_X_PERIODICITY
#define CAN_PREVENT_Y_PERIODICITY

C--   disconnect tiles (no exchange between tiles, just fill-in edges
C     assuming locally periodic subdomain)
#undef DISCONNECTED_TILES

C--   Always cumulate tile local-sum in the same order by applying MPI allreduce
C     to array of tiles ; can get slower with large number of tiles (big set-up)
#define GLOBAL_SUM_ORDER_TILES

C--   Alternative way of doing global sum without MPI allreduce call
C     but instead, explicit MPI send & recv calls. Expected to be slower.
#undef GLOBAL_SUM_SEND_RECV

C--   Alternative way of doing global sum on a single CPU
C     to eliminate tiling-dependent roundoff errors. Note: This is slow.
#undef  CG2D_SINGLECPU_SUM

C=== Other options (to add/remove pieces of code) ===
C--   Flag to turn on checking for errors from all threads and procs
C     (calling S/R STOP_IF_ERROR) before stopping.
#define USE_ERROR_STOP

C--   Control use of communication with other component:
C     allow to import and export from/to Coupler interface.
#undef COMPONENT_MODULE

C--   Activate some pieces of code for coupling to GEOS AGCM
#undef HACK_FOR_GMAO_CPL

#endif /* _CPP_EEOPTIONS_H_ */

#include "CPP_EEMACROS.h"

1	jmc	1.43	C $Header: /u/gcmpack/MITgcm/eesupp/inc/CPP_EEOPTIONS.h,v 1.42 2017/08/09 15:18:49 mlosch Exp $
2	adcroft	1.17	C $Name: $
3
4	cnh	1.18	CBOP
5			C !ROUTINE: CPP_EEOPTIONS.h
6			C !INTERFACE:
7			C include "CPP_EEOPTIONS.h"
8	cnh	1.1	C
9	cnh	1.18	C !DESCRIPTION:
10			C ==========================================================
11	edhill	1.22	C \| CPP\_EEOPTIONS.h \|
12	cnh	1.18	C ==========================================================
13	cnh	1.1	C \| C preprocessor "execution environment" supporting \|
14			C \| flags. Use this file to set flags controlling the \|
15			C \| execution environment in which a model runs - as opposed \|
16			C \| to the dynamical problem the model solves. \|
17			C \| Note: Many options are implemented with both compile time\|
18			C \| and run-time switches. This allows options to be \|
19			C \| removed altogether, made optional at run-time or \|
20			C \| to be permanently enabled. This convention helps \|
21			C \| with the data-dependence analysis performed by the \|
22			C \| adjoint model compiler. This data dependency \|
23			C \| analysis can be upset by runtime switches that it \|
24			C \| is unable to recoginise as being fixed for the \|
25			C \| duration of an integration. \|
26			C \| A reasonable way to use these flags is to \|
27			C \| set all options as selectable at runtime but then \|
28			C \| once an experimental configuration has been \|
29			C \| identified, rebuild the code with the appropriate \|
30			C \| options set at compile time. \|
31	cnh	1.18	C ==========================================================
32			CEOP
33	cnh	1.1
34	adcroft	1.4	#ifndef _CPP_EEOPTIONS_H_
35			#define _CPP_EEOPTIONS_H_
36
37	cnh	1.1	C In general the following convention applies:
38			C ALLOW - indicates an feature will be included but it may
39			C CAN have a run-time flag to allow it to be switched
40			C on and off.
41			C If ALLOW or CAN directives are "undef'd" this generally
42			C means that the feature will not be available i.e. it
43			C will not be included in the compiled code and so no
44			C run-time option to use the feature will be available.
45			C
46			C ALWAYS - indicates the choice will be fixed at compile time
47			C so no run-time option will be present
48
49	jmc	1.33	C=== Macro related options ===
50			C-- Control storage of floating point operands
51			C On many systems it improves performance only to use
52			C 8-byte precision for time stepped variables.
53			C Constant in time terms ( geometric factors etc.. )
54			C can use 4-byte precision, reducing memory utilisation and
55			C boosting performance because of a smaller working set size.
56			C However, on vector CRAY systems this degrades performance.
57			C Enable to switch REAL4_IS_SLOW from genmake2 (with LET_RS_BE_REAL4):
58			#ifdef LET_RS_BE_REAL4
59			#undef REAL4_IS_SLOW
60			#else /* LET_RS_BE_REAL4 */
61			#define REAL4_IS_SLOW
62			#endif /* LET_RS_BE_REAL4 */
63
64			C-- Control use of "double" precision constants.
65			C Use D0 where it means REAL8 but not where it means REAL16
66			#define D0 d0
67
68			C-- Enable some old macro conventions for backward compatibility
69			#undef USE_OLD_MACROS_R4R8toRSRL
70
71			C=== IO related options ===
72	jmc	1.25	C-- Flag used to indicate whether Fortran formatted write
73	cnh	1.1	C and read are threadsafe. On SGI the routines can be thread
74			C safe, on Sun it is not possible - if you are unsure then
75			C undef this option.
76	jmc	1.25	#undef FMTFTN_IO_THREAD_SAFE
77
78			C-- Flag used to indicate whether Binary write to Local file (i.e.,
79			C a different file for each tile) and read are thread-safe.
80			#undef LOCBIN_IO_THREAD_SAFE
81
82			C-- Flag to turn off the writing of error message to ioUnit zero
83			#undef DISABLE_WRITE_TO_UNIT_ZERO
84	cnh	1.1
85	jmc	1.33	C-- Alternative formulation of BYTESWAP, faster than
86			C compiler flag -byteswapio on the Altix.
87			#undef FAST_BYTESWAP
88	jmc	1.30
89	mlosch	1.42	C-- Flag to turn on old default of opening scratch files with the
90			C STATUS='SCRATCH' option. This method, while perfectly FORTRAN-standard,
91			C caused filename conflicts on some multi-node/multi-processor platforms
92			C in the past and has been replace by something (hopefully) more robust.
93			#undef USE_FORTRAN_SCRATCH_FILES
94
95	jmc	1.39	C-- Flag defined for eeboot_minimal.F, eeset_parms.F and open_copy_data_file.F
96			C to write STDOUT, STDERR and scratch files from process 0 only.
97	jmc	1.38	C WARNING: to use only when absolutely confident that the setup is working
98			C since any message (error/warning/print) from any proc <> 0 will be lost.
99	dimitri	1.36	#undef SINGLE_DISK_IO
100
101	jmc	1.33	C=== MPI, EXCH and GLOBAL_SUM related options ===
102	dimitri	1.26	C-- Flag turns off MPI_SEND ready_to_receive polling in the
103			C gather_* subroutines to speed up integrations.
104			#undef DISABLE_MPI_READY_TO_RECEIVE
105
106	cnh	1.1	C-- Control MPI based parallel processing
107	adcroft	1.19	CXXX We no longer select the use of MPI via this file (CPP_EEOPTIONS.h)
108			CXXX To use MPI, use an appropriate genmake2 options file or use
109			CXXX genmake2 -mpi .
110			CXXX #undef ALLOW_USE_MPI
111	jmc	1.25
112	cnh	1.1	C-- Control use of communication that might overlap computation.
113			C Under MPI selects/deselects "non-blocking" sends and receives.
114			#define ALLOW_ASYNC_COMMUNICATION
115			#undef ALLOW_ASYNC_COMMUNICATION
116			#undef ALWAYS_USE_ASYNC_COMMUNICATION
117			C-- Control use of communication that is atomic to computation.
118			C Under MPI selects/deselects "blocking" sends and receives.
119			#define ALLOW_SYNC_COMMUNICATION
120			#undef ALWAYS_USE_SYNC_COMMUNICATION
121	adcroft	1.13
122	cnh	1.1	C-- Control XY periodicity in processor to grid mappings
123	jmc	1.25	C Note: Model code does not need to know whether a domain is
124	cnh	1.1	C periodic because it has overlap regions for every box.
125	cnh	1.10	C Model assume that these values have been
126	cnh	1.1	C filled in some way.
127			#undef ALWAYS_PREVENT_X_PERIODICITY
128			#undef ALWAYS_PREVENT_Y_PERIODICITY
129			#define CAN_PREVENT_X_PERIODICITY
130			#define CAN_PREVENT_Y_PERIODICITY
131
132	jmc	1.34	C-- disconnect tiles (no exchange between tiles, just fill-in edges
133			C assuming locally periodic subdomain)
134			#undef DISCONNECTED_TILES
135
136	jmc	1.40	C-- Always cumulate tile local-sum in the same order by applying MPI allreduce
137			C to array of tiles ; can get slower with large number of tiles (big set-up)
138	jmc	1.41	#define GLOBAL_SUM_ORDER_TILES
139	jmc	1.40
140	jmc	1.28	C-- Alternative way of doing global sum without MPI allreduce call
141	jmc	1.40	C but instead, explicit MPI send & recv calls. Expected to be slower.
142	jmc	1.28	#undef GLOBAL_SUM_SEND_RECV
143
144	jahn	1.29	C-- Alternative way of doing global sum on a single CPU
145	jmc	1.40	C to eliminate tiling-dependent roundoff errors. Note: This is slow.
146	jahn	1.29	#undef CG2D_SINGLECPU_SUM
147
148	jmc	1.33	C=== Other options (to add/remove pieces of code) ===
149			C-- Flag to turn on checking for errors from all threads and procs
150			C (calling S/R STOP_IF_ERROR) before stopping.
151			#define USE_ERROR_STOP
152
153			C-- Control use of communication with other component:
154			C allow to import and export from/to Coupler interface.
155			#undef COMPONENT_MODULE
156	heimbach	1.32
157	jmc	1.43	C-- Activate some pieces of code for coupling to GEOS AGCM
158			#undef HACK_FOR_GMAO_CPL
159
160	adcroft	1.14	#endif /* _CPP_EEOPTIONS_H_ */
161	cnh	1.3
162	adcroft	1.14	#include "CPP_EEMACROS.h"
163	edhill	1.23