Contents of /MITgcm/doc/README

$Header: /u/gcmpack/models/MITgcmUV/doc/README,v 1.8 1998/06/22 16:24:50 adcroft Exp $


MITgcmUV Getting Started
========================

o Introduction

  This note is a guide to using the MIT General Circulation Model Ultra Verstaile
  implementation, MITgmcUV. MITgcmUV is a Fortran code that implements the 
  algorithm described in Marshall et. al. 1997, Hill, Adcroft, ...
   The MITgcmUV implementation is designed to work efficiently on all classes
  of computer platforms. It can be used in both a single processor mode
  and a parallel processor mode. Parallel processing can be either multi-threaded
  shared memory such as that found on CRAY T90 machines or it can be multi-process
  distributed memory. A set of "execution enviroment" support routines are 
  used to allow the same numerical code to run on top of a single-process, multi-threaded
  or distributed multi-process configuration.

o Installing
  To setup the model on a particular computer the code tree must be created
  and appropriate compile and run scripts set up. For some platforms
  the necessary scripts are included in the release - in this case follow
  the steps below:

  1. Extract MITgcmUV from the downloadable archive
     tar -xvf checkpoint12.tar 

  2. Create platform specific make file
     For example on a Digital UNIX machine the script "genmake.dec" can
     be used as shown below

     cd bin
     ../tools/genmake 
     cp Makefile.alpha Makefile

  3. Now create header file dependency entries
     make depend

  4. Compile code
     make

  5. Copy input files
     cp ../verification/exp2/[a-z]* ../verification/exp2/*bin .
  
  6. Run baseline test case
     setenv PARALLEL 1
     dmpirun -np 2 ../exe/mitgcmuv

     This runs a 4 degree global ocean climatological simulation.
     By default this code is set to use two porcessors splitting
     the model domain along the equator. Textual output is written
     to files STDOUT.* and STDERR.* with one file for each process.
     Model fileds are written to files suffixed .data and .meta
     These files are written on a per process basis. The .meta
     file indicates the location and shape of the subdomain in
     each .data file.

o Running

  - Input and output files

    Required files
    ==============
    The model is configured to look for two files with fixed names.
    These files are called
     "eedata" and "data".
    The file eedata contains "execution environment" data. At present
    this consists of a specification of the number of threads to
    use in X and Y under multithreaded execution.

  - Serial execution

  - Parallel execution. Threads
    nSx, nSy
    setenv PARALLEL n
    nTx=2, nTy=2

  - Parallel execution. MPI
    mPx, nPy
    dmpirun

  - Parallel execution. Hybrid

o References
  Web sites - HP
  for doc     Digital
              SGI
              Sun
              Linux threads
              CRAY multitasking
              PPT notes
1	$Header: /u/gcmpack/models/MITgcmUV/doc/README,v 1.8 1998/06/22 16:24:50 adcroft Exp $
2
3
4	MITgcmUV Getting Started
5	========================
6
7	o Introduction
8
9	This note is a guide to using the MIT General Circulation Model Ultra Verstaile
10	implementation, MITgmcUV. MITgcmUV is a Fortran code that implements the
11	algorithm described in Marshall et. al. 1997, Hill, Adcroft, ...
12	The MITgcmUV implementation is designed to work efficiently on all classes
13	of computer platforms. It can be used in both a single processor mode
14	and a parallel processor mode. Parallel processing can be either multi-threaded
15	shared memory such as that found on CRAY T90 machines or it can be multi-process
16	distributed memory. A set of "execution enviroment" support routines are
17	used to allow the same numerical code to run on top of a single-process, multi-threaded
18	or distributed multi-process configuration.
19
20	o Installing
21	To setup the model on a particular computer the code tree must be created
22	and appropriate compile and run scripts set up. For some platforms
23	the necessary scripts are included in the release - in this case follow
24	the steps below:
25
26	1. Extract MITgcmUV from the downloadable archive
27	tar -xvf checkpoint12.tar
28
29	2. Create platform specific make file
30	For example on a Digital UNIX machine the script "genmake.dec" can
31	be used as shown below
32
33	cd bin
34	../tools/genmake
35	cp Makefile.alpha Makefile
36
37	3. Now create header file dependency entries
38	make depend
39
40	4. Compile code
41	make
42
43	5. Copy input files
44	cp ../verification/exp2/[a-z]* ../verification/exp2/*bin .
45
46	6. Run baseline test case
47	setenv PARALLEL 1
48	dmpirun -np 2 ../exe/mitgcmuv
49
50	This runs a 4 degree global ocean climatological simulation.
51	By default this code is set to use two porcessors splitting
52	the model domain along the equator. Textual output is written
53	to files STDOUT.* and STDERR.* with one file for each process.
54	Model fileds are written to files suffixed .data and .meta
55	These files are written on a per process basis. The .meta
56	file indicates the location and shape of the subdomain in
57	each .data file.
58
59	o Running
60
61	- Input and output files
62
63	Required files
64	==============
65	The model is configured to look for two files with fixed names.
66	These files are called
67	"eedata" and "data".
68	The file eedata contains "execution environment" data. At present
69	this consists of a specification of the number of threads to
70	use in X and Y under multithreaded execution.
71
72	- Serial execution
73
74	- Parallel execution. Threads
75	nSx, nSy
76	setenv PARALLEL n
77	nTx=2, nTy=2
78
79	- Parallel execution. MPI
80	mPx, nPy
81	dmpirun
82
83	- Parallel execution. Hybrid
84
85	o References
86	Web sites - HP
87	for doc Digital
88	SGI
89	Sun
90	Linux threads
91	CRAY multitasking
92	PPT notes