1 |
C $Header: /u/gcmpack/MITgcm/eesupp/inc/CPP_EEOPTIONS.h,v 1.27 2006/11/22 09:43:27 dimitri Exp $ |
2 |
C $Name: $ |
3 |
|
4 |
CBOP |
5 |
C !ROUTINE: CPP_EEOPTIONS.h |
6 |
C !INTERFACE: |
7 |
C include "CPP_EEOPTIONS.h" |
8 |
C |
9 |
C !DESCRIPTION: |
10 |
C *==========================================================* |
11 |
C | CPP\_EEOPTIONS.h | |
12 |
C *==========================================================* |
13 |
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 |
C *==========================================================* |
32 |
CEOP |
33 |
|
34 |
#ifndef _CPP_EEOPTIONS_H_ |
35 |
#define _CPP_EEOPTIONS_H_ |
36 |
|
37 |
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 |
C-- Flag used to indicate whether Fortran formatted write |
50 |
C and read are threadsafe. On SGI the routines can be thread |
51 |
C safe, on Sun it is not possible - if you are unsure then |
52 |
C undef this option. |
53 |
#undef FMTFTN_IO_THREAD_SAFE |
54 |
|
55 |
C-- Flag used to indicate whether Binary write to Local file (i.e., |
56 |
C a different file for each tile) and read are thread-safe. |
57 |
#undef LOCBIN_IO_THREAD_SAFE |
58 |
|
59 |
C-- Flag to turn off the writing of error message to ioUnit zero |
60 |
#undef DISABLE_WRITE_TO_UNIT_ZERO |
61 |
|
62 |
C-- Flag turns off MPI_SEND ready_to_receive polling in the |
63 |
C gather_* subroutines to speed up integrations. |
64 |
#undef DISABLE_MPI_READY_TO_RECEIVE |
65 |
|
66 |
C-- Control MPI based parallel processing |
67 |
CXXX We no longer select the use of MPI via this file (CPP_EEOPTIONS.h) |
68 |
CXXX To use MPI, use an appropriate genmake2 options file or use |
69 |
CXXX genmake2 -mpi . |
70 |
CXXX #undef ALLOW_USE_MPI |
71 |
CXXX #undef ALWAYS_USE_MPI |
72 |
|
73 |
C-- Control use of communication that might overlap computation. |
74 |
C Under MPI selects/deselects "non-blocking" sends and receives. |
75 |
#define ALLOW_ASYNC_COMMUNICATION |
76 |
#undef ALLOW_ASYNC_COMMUNICATION |
77 |
#undef ALWAYS_USE_ASYNC_COMMUNICATION |
78 |
C-- Control use of communication that is atomic to computation. |
79 |
C Under MPI selects/deselects "blocking" sends and receives. |
80 |
#define ALLOW_SYNC_COMMUNICATION |
81 |
#undef ALWAYS_USE_SYNC_COMMUNICATION |
82 |
|
83 |
C-- Control use of JAM routines for Artic network |
84 |
C These invoke optimized versions of "exchange" and "sum" that |
85 |
C utilize the programmable aspect of Artic cards. |
86 |
#undef LETS_MAKE_JAM |
87 |
#undef JAM_WITH_TWO_PROCS_PER_NODE |
88 |
|
89 |
C-- Control storage of floating point operands |
90 |
C On many systems it improves performance only to use |
91 |
C 8-byte precision for time stepped variables. |
92 |
C Constant in time terms ( geometric factors etc.. ) |
93 |
C can use 4-byte precision, reducing memory utilisation and |
94 |
C boosting performance because of a smaller working |
95 |
C set size. However, on vector CRAY systems this degrades |
96 |
C performance. |
97 |
#define REAL4_IS_SLOW |
98 |
|
99 |
C-- Control use of "double" precision constants. |
100 |
C Use D0 where it means REAL*8 but not where it means REAL*16 |
101 |
#define D0 d0 |
102 |
|
103 |
C-- Control XY periodicity in processor to grid mappings |
104 |
C Note: Model code does not need to know whether a domain is |
105 |
C periodic because it has overlap regions for every box. |
106 |
C Model assume that these values have been |
107 |
C filled in some way. |
108 |
#undef ALWAYS_PREVENT_X_PERIODICITY |
109 |
#undef ALWAYS_PREVENT_Y_PERIODICITY |
110 |
#define CAN_PREVENT_X_PERIODICITY |
111 |
#define CAN_PREVENT_Y_PERIODICITY |
112 |
|
113 |
C-- Alternative formulation of BYTESWAP, faster than |
114 |
C compiler flag -byteswapio on the Altix. |
115 |
#undef FAST_BYTESWAP |
116 |
|
117 |
C-- Alternative way of doing global sum without MPI allreduce call |
118 |
C but instead, explicit MPI send & recv calls. |
119 |
#undef GLOBAL_SUM_SEND_RECV |
120 |
|
121 |
#endif /* _CPP_EEOPTIONS_H_ */ |
122 |
|
123 |
#include "CPP_EEMACROS.h" |
124 |
|