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File indexing completed on 2024-11-26 06:11:50 UTC
view on githubraw file Latest commit 27ce1202 on 2024-11-25 17:10:12 UTC910e5c3e29 Mart*0001 #ifndef _CPP_EEOPTIONS_H_ 0002 #define _CPP_EEOPTIONS_H_ 0003 b4daa24319 Shre*0004 CBOP 0005 C !ROUTINE: CPP_EEOPTIONS.h 0006 C !INTERFACE: 0007 C include "CPP_EEOPTIONS.h" 0008 C 0009 C !DESCRIPTION: 0010 C *==========================================================* 0011 C | CPP\_EEOPTIONS.h | 0012 C *==========================================================* 0013 C | C preprocessor "execution environment" supporting | 0014 C | flags. Use this file to set flags controlling the | 0015 C | execution environment in which a model runs - as opposed | 0016 C | to the dynamical problem the model solves. | 0017 C | Note: Many options are implemented with both compile time| 0018 C | and run-time switches. This allows options to be | 0019 C | removed altogether, made optional at run-time or | 0020 C | to be permanently enabled. This convention helps | 0021 C | with the data-dependence analysis performed by the | 0022 C | adjoint model compiler. This data dependency | 0023 C | analysis can be upset by runtime switches that it | 0024 C | is unable to recoginise as being fixed for the | 0025 C | duration of an integration. | 0026 C | A reasonable way to use these flags is to | 0027 C | set all options as selectable at runtime but then | 0028 C | once an experimental configuration has been | 0029 C | identified, rebuild the code with the appropriate | 0030 C | options set at compile time. | 0031 C *==========================================================* 0032 CEOP 0033 0034 C In general the following convention applies: 0035 C ALLOW - indicates an feature will be included but it may 0036 C CAN have a run-time flag to allow it to be switched 0037 C on and off. 0038 C If ALLOW or CAN directives are "undef'd" this generally 0039 C means that the feature will not be available i.e. it 0040 C will not be included in the compiled code and so no 0041 C run-time option to use the feature will be available. 0042 C 0043 C ALWAYS - indicates the choice will be fixed at compile time 0044 C so no run-time option will be present 0045 0046 C=== Macro related options === 0047 C-- Control storage of floating point operands 0048 C On many systems it improves performance only to use 0049 C 8-byte precision for time stepped variables. 0050 C Constant in time terms ( geometric factors etc.. ) 0051 C can use 4-byte precision, reducing memory utilisation and 0052 C boosting performance because of a smaller working set size. 0053 C However, on vector CRAY systems this degrades performance. 0054 C Enable to switch REAL4_IS_SLOW from genmake2 (with LET_RS_BE_REAL4): 0055 #ifdef LET_RS_BE_REAL4 0056 #undef REAL4_IS_SLOW 0057 #else /* LET_RS_BE_REAL4 */ 0058 #define REAL4_IS_SLOW 0059 #endif /* LET_RS_BE_REAL4 */ 0060 0061 C-- Control use of "double" precision constants. 0062 C Use D0 where it means REAL*8 but not where it means REAL*16 0063 #define D0 d0 0064 0065 C=== IO related options === 0066 C-- Flag used to indicate whether Fortran formatted write 0067 C and read are threadsafe. On SGI the routines can be thread 0068 C safe, on Sun it is not possible - if you are unsure then 0069 C undef this option. 0070 #undef FMTFTN_IO_THREAD_SAFE 0071 0072 C-- Flag used to indicate whether Binary write to Local file (i.e., 0073 C a different file for each tile) and read are thread-safe. 0074 #undef LOCBIN_IO_THREAD_SAFE 0075 0076 C-- Flag to turn off the writing of error message to ioUnit zero 0077 #undef DISABLE_WRITE_TO_UNIT_ZERO 0078 0079 C-- Flag to turn on old default of opening scratch files with the 0080 C STATUS='SCRATCH' option. This method, while perfectly FORTRAN-standard, 0081 C caused filename conflicts on some multi-node/multi-processor platforms 0082 C in the past and has been replace by something (hopefully) more robust. 0083 #define USE_FORTRAN_SCRATCH_FILES 0084 0085 C-- Flag defined for eeboot_minimal.F, eeset_parms.F and open_copy_data_file.F 0086 C to write STDOUT, STDERR and scratch files from process 0 only. 0087 C WARNING: to use only when absolutely confident that the setup is working 0088 C since any message (error/warning/print) from any proc <> 0 will be lost. 0089 #undef SINGLE_DISK_IO 0090 0091 C=== MPI, EXCH and GLOBAL_SUM related options === 0092 C-- Flag turns off MPI_SEND ready_to_receive polling in the 0093 C gather_* subroutines to speed up integrations. 0094 #undef DISABLE_MPI_READY_TO_RECEIVE 0095 0096 C-- Control use of communication that might overlap computation. 0097 C Under MPI selects/deselects "non-blocking" sends and receives. 0098 #undef ALLOW_ASYNC_COMMUNICATION 0099 #undef ALWAYS_USE_ASYNC_COMMUNICATION 0100 C-- Control use of communication that is atomic to computation. 0101 C Under MPI selects/deselects "blocking" sends and receives. 0102 #define ALLOW_SYNC_COMMUNICATION 0103 #undef ALWAYS_USE_SYNC_COMMUNICATION 0104 0105 C-- Control XY periodicity in processor to grid mappings 0106 C Note: Model code does not need to know whether a domain is 0107 C periodic because it has overlap regions for every box. 0108 C Model assume that these values have been 0109 C filled in some way. 0110 #undef ALWAYS_PREVENT_X_PERIODICITY 0111 #undef ALWAYS_PREVENT_Y_PERIODICITY 0112 #define CAN_PREVENT_X_PERIODICITY 0113 #define CAN_PREVENT_Y_PERIODICITY 0114 0115 C-- disconnect tiles (no exchange between tiles, just fill-in edges 0116 C assuming locally periodic subdomain) 0117 #undef DISCONNECTED_TILES 0118 0119 C-- Always cumulate tile local-sum in the same order by applying MPI allreduce 0120 C to array of tiles ; can get slower with large number of tiles (big set-up) 0121 #undef GLOBAL_SUM_ORDER_TILES 0122 0123 C-- Alternative way of doing global sum without MPI allreduce call 0124 C but instead, explicit MPI send & recv calls. Expected to be slower. 0125 #define GLOBAL_SUM_SEND_RECV 0126 0127 C-- Alternative way of doing global sum on a single CPU 0128 C to eliminate tiling-dependent roundoff errors. Note: This is slow. 0129 #define CG2D_SINGLECPU_SUM 0130 0131 C=== Other options (to add/remove pieces of code) === 0132 C-- Flag to turn on checking for errors from all threads and procs 0133 C (calling S/R STOP_IF_ERROR) before stopping. 0134 #define USE_ERROR_STOP 0135 0136 C-- Control use of communication with other component: 0137 C allow to import and export from/to Coupler interface. 0138 #undef COMPONENT_MODULE 0139 910e5c3e29 Mart*0140 C-- Activate some pieces of code for coupling to GEOS AGCM 0141 #undef HACK_FOR_GMAO_CPL b4daa24319 Shre*0142 910e5c3e29 Mart*0143 C=== And define Macros === b4daa24319 Shre*0144 #include "CPP_EEMACROS.h" 0145 910e5c3e29 Mart*0146 #endif /* _CPP_EEOPTIONS_H_ */
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