eesupp/src/main.F

C $Header: /u/gcmpack/models/MITgcmUV/eesupp/src/main.F,v 1.8 2001/09/21 03:54:35 cnh Exp $
C $Name:  $

CBOI
C
C !TITLE: WRAPPER CODE SYNOPSIS
C !AUTHORS: mitgcm developers ( support@mitgcm.org )
C !AFFILIATION: Massachussetts Institute of Technology
C !DATE:
C !INTRODUCTION: Wrapper synopsis and code
C Routines in the subdirectories under eesupp/ ( src/ and inc/ ) provide the core
C framework within which numerical and ancilliary software of MITgcm operates.
C The eesupp/ directories provide a collection of software we call {\bf WRAPPER} (
C ({\bf W}rappable {\bf A}pplication {\bf P}aralell {\bf P}rogramming {\bf E}nvironment {\bf R}esource).
C The {bf WRAPPER} provides a generic bootstrapping capability to start applications
C in a manner that allows them to exploit single and multi-processing environments on all present 
C day hardware platforms (spanning vector SMP systems to distributed memory and processing cluster
C systems). Numerical applications must be coded to fit within the {\bf WRAPPER}. This entails
C applications adopting a particular style for declaring data structures representing
C grids and values on grids. The {\bf WRAPPER} currently provides support for grid point
C models using a single global indexing system. This is sufficient for latitude-logitude,
C cylindrical, and cartesian coordinate configurations. There is also limited support for
C composing grids in which no single, sructured global index can be defined. At present, this 
C support is limited to specific configurations of projections of a cube onto the sphere.
C
C The main functions supported by the current {\bf WRAPPER} code are
C \begin{itemize}
C  \item program startup and termination including creation/management of multiple 
C        threads and/or processes
C  \item communication and synchronisatioin operations between multiple processes and/or threads 
C  \item multi-process input and output operations to disk and to other 
C  applications
C \end{itemize}
C
C Multi-process execution assumes the existence of MPI for process startup and termination. However,
C MPI does not have to be used for performance critical operations. Instead,
C {\bf WRAPPER} performance critical parallel primitives are implemented to allow them to bind to 
C different low-level system software layers. Bindings exist for using {\bf WRAPPER} with portable
C systems such as MPI and UNIX System V IPC memory mapping, as well bindings for high-performance 
C propreitary systems such as Myrinet GM software and Compaq IMC memory channel technology.
C 
CEOI


C--   Get C preprocessor options
#include "CPP_OPTIONS.h"
#include "CPP_EEOPTIONS.h"

CBOP
C !ROUTINE: MAIN

C !INTERFACE:
      PROGRAM MAIN
      IMPLICIT NONE

C !DESCRIPTION:
C     *==========================================================*
C     | PROGRAM MAIN                                            
C     | o MAIN wrapper for MITgcm UV implementation.            
C     *==========================================================*
C     | MAIN controls the "execution environment".               
C     | Its main functions are                                   
C     | 1. call procedure EEBOOT to perform execution environment
C     |    initialisation.                                       
C     | 2. call procedure THE_MODEL_MAIN once for each concurrent
C     |    thread. THE_MODEL_MAIN is the user supplied top-level 
C     |    routine.                                              
C     | 3. call procedure EEDIE to perform execution environment 
C     |    shutdown.                                             
C     *==========================================================*

C      !CALLING SEQUENCE:
C
C      main()       
C      |
C      |--eeboot()         :: WRAPPER initilization
C      |
C      |--check_threads()  :: Validate multiple thread start up.
C      |
C      |--the_model_main() :: Numerical code top-level driver routine
C      |
C      |--eedie()          :: WRAPPER termination

C     !USES:
C     == Global variables ==
C     Include all the "shared" data here. That means all common
C     blocks used in the model. On many implementations this is not
C     necessary but doing this is the safest method.
#include "SIZE.h"
#include "EEPARAMS.h"
#include "EESUPPORT.h"
#include "THE_MODEL_COMMON_BLOCKS.h"

C     !LOCAL VARIABLES:
C--   Local variables
      INTEGER myThid
      INTEGER I
CEOP

C--   Set up the execution environment
C     EEBOOT loads a execution environment parameter file 
C     ( called "eedata" by default ) and sets variables 
C     accordingly.
      CALL EEBOOT

C--   Trap errors 
      IF ( eeBootError ) THEN
       fatalError = .TRUE.
       GOTO 999
      ENDIF

C--   Start nThreads concurrent threads.   
C     Note: We do a fiddly check here. The check is performed
C           by CHECK_THREADS. CHECK_THREADS does a count
C           of all the threads. If after ten seconds it has not
C           found nThreads threads are running it flags an
C           error. This traps the case in which the input 
C           parameter nThreads is different from the actual 
C           number of concurrent threads the OS gives us. This
C           case causes a deadlock if we do not trap it here.
#include "MAIN_PDIRECTIVES1.h"
      DO I=1,nThreads
        myThid = I

C--     Do check to see if there are nThreads threads running
        IF ( .NOT. eeBootError ) THEN
         CALL CHECK_THREADS( myThid )
        ENDIF

C--     Invoke nThreads instances of the numerical model
        IF ( .NOT. eeBootError ) THEN
         CALL THE_MODEL_MAIN(myThid)
        ENDIF

C--     Each threads sets flag indicating it is done
        threadIsComplete(myThid) = .TRUE.
        IF ( .NOT. eeBootError ) THEN
         _BARRIER
        ENDIF
      ENDDO
#include "MAIN_PDIRECTIVES2.h"

  999 CONTINUE
C--   Shut down execution environment
      CALL EEDIE

C--   Write closedown status
      IF ( fatalError ) THEN
       STOP 'ABNORMAL END: PROGRAM MAIN'
      ELSE
       STOP 'NORMAL END'
      ENDIF
C
      END
1	C $Header: /u/gcmpack/models/MITgcmUV/eesupp/src/main.F,v 1.8 2001/09/21 03:54:35 cnh Exp $
2	C $Name: $
3
4	CBOI
5	C
6	C !TITLE: WRAPPER CODE SYNOPSIS
7	C !AUTHORS: mitgcm developers ( support@mitgcm.org )
8	C !AFFILIATION: Massachussetts Institute of Technology
9	C !DATE:
10	C !INTRODUCTION: Wrapper synopsis and code
11	C Routines in the subdirectories under eesupp/ ( src/ and inc/ ) provide the core
12	C framework within which numerical and ancilliary software of MITgcm operates.
13	C The eesupp/ directories provide a collection of software we call {\bf WRAPPER} (
14	C ({\bf W}rappable {\bf A}pplication {\bf P}aralell {\bf P}rogramming {\bf E}nvironment {\bf R}esource).
15	C The {bf WRAPPER} provides a generic bootstrapping capability to start applications
16	C in a manner that allows them to exploit single and multi-processing environments on all present
17	C day hardware platforms (spanning vector SMP systems to distributed memory and processing cluster
18	C systems). Numerical applications must be coded to fit within the {\bf WRAPPER}. This entails
19	C applications adopting a particular style for declaring data structures representing
20	C grids and values on grids. The {\bf WRAPPER} currently provides support for grid point
21	C models using a single global indexing system. This is sufficient for latitude-logitude,
22	C cylindrical, and cartesian coordinate configurations. There is also limited support for
23	C composing grids in which no single, sructured global index can be defined. At present, this
24	C support is limited to specific configurations of projections of a cube onto the sphere.
25	C
26	C The main functions supported by the current {\bf WRAPPER} code are
27	C \begin{itemize}
28	C \item program startup and termination including creation/management of multiple
29	C threads and/or processes
30	C \item communication and synchronisatioin operations between multiple processes and/or threads
31	C \item multi-process input and output operations to disk and to other
32	C applications
33	C \end{itemize}
34	C
35	C Multi-process execution assumes the existence of MPI for process startup and termination. However,
36	C MPI does not have to be used for performance critical operations. Instead,
37	C {\bf WRAPPER} performance critical parallel primitives are implemented to allow them to bind to
38	C different low-level system software layers. Bindings exist for using {\bf WRAPPER} with portable
39	C systems such as MPI and UNIX System V IPC memory mapping, as well bindings for high-performance
40	C propreitary systems such as Myrinet GM software and Compaq IMC memory channel technology.
41	C
42	CEOI
43
44
45	C-- Get C preprocessor options
46	#include "CPP_OPTIONS.h"
47	#include "CPP_EEOPTIONS.h"
48
49	CBOP
50	C !ROUTINE: MAIN
51
52	C !INTERFACE:
53	PROGRAM MAIN
54	IMPLICIT NONE
55
56	C !DESCRIPTION:
57	C ==========================================================
58	C \| PROGRAM MAIN
59	C \| o MAIN wrapper for MITgcm UV implementation.
60	C ==========================================================
61	C \| MAIN controls the "execution environment".
62	C \| Its main functions are
63	C \| 1. call procedure EEBOOT to perform execution environment
64	C \| initialisation.
65	C \| 2. call procedure THE_MODEL_MAIN once for each concurrent
66	C \| thread. THE_MODEL_MAIN is the user supplied top-level
67	C \| routine.
68	C \| 3. call procedure EEDIE to perform execution environment
69	C \| shutdown.
70	C ==========================================================
71
72	C !CALLING SEQUENCE:
73	C
74	C main()
75	C \|
76	C \|--eeboot() :: WRAPPER initilization
77	C \|
78	C \|--check_threads() :: Validate multiple thread start up.
79	C \|
80	C \|--the_model_main() :: Numerical code top-level driver routine
81	C \|
82	C \|--eedie() :: WRAPPER termination
83
84	C !USES:
85	C == Global variables ==
86	C Include all the "shared" data here. That means all common
87	C blocks used in the model. On many implementations this is not
88	C necessary but doing this is the safest method.
89	#include "SIZE.h"
90	#include "EEPARAMS.h"
91	#include "EESUPPORT.h"
92	#include "THE_MODEL_COMMON_BLOCKS.h"
93
94	C !LOCAL VARIABLES:
95	C-- Local variables
96	INTEGER myThid
97	INTEGER I
98	CEOP
99
100	C-- Set up the execution environment
101	C EEBOOT loads a execution environment parameter file
102	C ( called "eedata" by default ) and sets variables
103	C accordingly.
104	CALL EEBOOT
105
106	C-- Trap errors
107	IF ( eeBootError ) THEN
108	fatalError = .TRUE.
109	GOTO 999
110	ENDIF
111
112	C-- Start nThreads concurrent threads.
113	C Note: We do a fiddly check here. The check is performed
114	C by CHECK_THREADS. CHECK_THREADS does a count
115	C of all the threads. If after ten seconds it has not
116	C found nThreads threads are running it flags an
117	C error. This traps the case in which the input
118	C parameter nThreads is different from the actual
119	C number of concurrent threads the OS gives us. This
120	C case causes a deadlock if we do not trap it here.
121	#include "MAIN_PDIRECTIVES1.h"
122	DO I=1,nThreads
123	myThid = I
124
125	C-- Do check to see if there are nThreads threads running
126	IF ( .NOT. eeBootError ) THEN
127	CALL CHECK_THREADS( myThid )
128	ENDIF
129
130	C-- Invoke nThreads instances of the numerical model
131	IF ( .NOT. eeBootError ) THEN
132	CALL THE_MODEL_MAIN(myThid)
133	ENDIF
134
135	C-- Each threads sets flag indicating it is done
136	threadIsComplete(myThid) = .TRUE.
137	IF ( .NOT. eeBootError ) THEN
138	_BARRIER
139	ENDIF
140	ENDDO
141	#include "MAIN_PDIRECTIVES2.h"
142
143	999 CONTINUE
144	C-- Shut down execution environment
145	CALL EEDIE
146
147	C-- Write closedown status
148	IF ( fatalError ) THEN
149	STOP 'ABNORMAL END: PROGRAM MAIN'
150	ELSE
151	STOP 'NORMAL END'
152	ENDIF
153	C
154	END