/[MITgcm]/MITgcm/eesupp/inc/CPP_EEOPTIONS.h
ViewVC logotype

Contents of /MITgcm/eesupp/inc/CPP_EEOPTIONS.h

Parent Directory Parent Directory | Revision Log Revision Log | View Revision Graph Revision Graph


Revision 1.28 - (show annotations) (download)
Tue Sep 4 14:40:08 2007 UTC (17 years, 3 months ago) by jmc
Branch: MAIN
CVS Tags: checkpoint59g, checkpoint59l, checkpoint59i, checkpoint59h, checkpoint59k, checkpoint59j
Changes since 1.27: +5 -1 lines
File MIME type: text/plain
add option for Alternative way of doing global sum,
without MPI allreduce call but instead, explicit MPI send & recv calls.

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

  ViewVC Help
Powered by ViewVC 1.1.22