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Warning, /verification/exp4/code/CPP_EEOPTIONS.h_mpi is written in an unsupported language. File is not indexed.

view on githubraw file Latest commit add29e06 on 2018-01-31 20:35:05 UTC
5c3d07dc7a Jean*0001 CBOP
                0002 C     !ROUTINE: CPP_EEOPTIONS.h
                0003 C     !INTERFACE:
                0004 C     include "CPP_EEOPTIONS.h"
                0005 C
                0006 C     !DESCRIPTION:
                0007 C     *==========================================================*
                0008 C     | CPP\_EEOPTIONS.h                                         |
                0009 C     *==========================================================*
                0010 C     | C preprocessor "execution environment" supporting        |
                0011 C     | flags. Use this file to set flags controlling the        |
                0012 C     | execution environment in which a model runs - as opposed |
                0013 C     | to the dynamical problem the model solves.               |
                0014 C     | Note: Many options are implemented with both compile time|
                0015 C     |       and run-time switches. This allows options to be   |
                0016 C     |       removed altogether, made optional at run-time or   |
                0017 C     |       to be permanently enabled. This convention helps   |
                0018 C     |       with the data-dependence analysis performed by the |
                0019 C     |       adjoint model compiler. This data dependency       |
                0020 C     |       analysis can be upset by runtime switches that it  |
                0021 C     |       is unable to recoginise as being fixed for the     |
                0022 C     |       duration of an integration.                        |
                0023 C     |       A reasonable way to use these flags is to          |
                0024 C     |       set all options as selectable at runtime but then  |
                0025 C     |       once an experimental configuration has been        |
                0026 C     |       identified, rebuild the code with the appropriate  |
                0027 C     |       options set at compile time.                       |
                0028 C     *==========================================================*
                0029 CEOP
                0030 
                0031 #ifndef _CPP_EEOPTIONS_H_
                0032 #define _CPP_EEOPTIONS_H_
                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 
b854e76171 Jean*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 ===
5c3d07dc7a Jean*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 
b854e76171 Jean*0079 C--   Alternative formulation of BYTESWAP, faster than
                0080 C     compiler flag -byteswapio on the Altix.
                0081 #undef FAST_BYTESWAP
5c3d07dc7a Jean*0082 
3310c7d649 Jean*0083 C--   Flag defined for eeboot_minimal.F, eeset_parms.F and open_copy_data_file.F
                0084 C     to write STDOUT, STDERR and scratch files from process 0 only.
                0085 C WARNING: to use only when absolutely confident that the setup is working
                0086 C     since any message (error/warning/print) from any proc <> 0 will be lost.
                0087 #undef SINGLE_DISK_IO
                0088 
b854e76171 Jean*0089 C=== MPI, EXCH and GLOBAL_SUM related options ===
5c3d07dc7a Jean*0090 C--   Flag turns off MPI_SEND ready_to_receive polling in the
                0091 C     gather_* subroutines to speed up integrations.
                0092 #undef DISABLE_MPI_READY_TO_RECEIVE
                0093 
                0094 C--   Control use of communication that might overlap computation.
                0095 C     Under MPI selects/deselects "non-blocking" sends and receives.
                0096 #define ALLOW_ASYNC_COMMUNICATION
                0097 #undef  ALLOW_ASYNC_COMMUNICATION
                0098 #undef  ALWAYS_USE_ASYNC_COMMUNICATION
                0099 C--   Control use of communication that is atomic to computation.
                0100 C     Under MPI selects/deselects "blocking" sends and receives.
                0101 #define ALLOW_SYNC_COMMUNICATION
                0102 #undef  ALWAYS_USE_SYNC_COMMUNICATION
                0103 
                0104 C--   Control XY periodicity in processor to grid mappings
                0105 C     Note: Model code does not need to know whether a domain is
                0106 C           periodic because it has overlap regions for every box.
                0107 C           Model assume that these values have been
                0108 C           filled in some way.
                0109 #undef  ALWAYS_PREVENT_X_PERIODICITY
                0110 #undef  ALWAYS_PREVENT_Y_PERIODICITY
                0111 #define CAN_PREVENT_X_PERIODICITY
                0112 #define CAN_PREVENT_Y_PERIODICITY
                0113 
3310c7d649 Jean*0114 C--   disconnect tiles (no exchange between tiles, just fill-in edges
                0115 C     assuming locally periodic subdomain)
                0116 #undef DISCONNECTED_TILES
                0117 
                0118 C--   Always cumulate tile local-sum in the same order by applying MPI allreduce
                0119 C     to array of tiles ; can get slower with large number of tiles (big set-up)
                0120 #undef GLOBAL_SUM_ORDER_TILES
                0121 
5c3d07dc7a Jean*0122 C--   Alternative way of doing global sum without MPI allreduce call
3310c7d649 Jean*0123 C     but instead, explicit MPI send & recv calls. Expected to be slower.
5c3d07dc7a Jean*0124 #define GLOBAL_SUM_SEND_RECV
                0125 
                0126 C--   Alternative way of doing global sum on a single CPU
3310c7d649 Jean*0127 C     to eliminate tiling-dependent roundoff errors. Note: This is slow.
5c3d07dc7a Jean*0128 #undef  CG2D_SINGLECPU_SUM
                0129 
b854e76171 Jean*0130 C=== Other options (to add/remove pieces of code) ===
                0131 C--   Flag to turn on checking for errors from all threads and procs
                0132 C     (calling S/R STOP_IF_ERROR) before stopping.
                0133 #define USE_ERROR_STOP
                0134 
                0135 C--   Control use of communication with other component:
                0136 C     allow to import and export from/to Coupler interface.
                0137 #undef COMPONENT_MODULE
                0138 
5c3d07dc7a Jean*0139 #endif /* _CPP_EEOPTIONS_H_ */
                0140 
                0141 #include "CPP_EEMACROS.h"
                0142