| 1 | jmc | 1.40 | % $Header: /u/gcmpack/manual/part3/getting_started.tex,v 1.39 2006/06/30 15:56:52 molod Exp $ | 
| 2 | adcroft | 1.2 | % $Name:  $ | 
| 3 | adcroft | 1.1 |  | 
| 4 | adcroft | 1.4 | %\section{Getting started} | 
| 5 | adcroft | 1.1 |  | 
| 6 | molod | 1.39 | We believe the best way to familiarize yourself with the | 
| 7 | adcroft | 1.4 | model is to run the case study examples provided with the base | 
| 8 |  |  | version. Information on how to obtain, compile, and run the code is | 
| 9 | molod | 1.39 | found here as well as a brief description of the model structure | 
| 10 |  |  | directory and the case study examples. Information is also provided | 
| 11 |  |  | here on how to customize the code when you are ready to try implementing | 
| 12 |  |  | the configuration you have in mind.  The code and algorithm | 
| 13 |  |  | are described more fully in chapters \ref{chap:discretization} and | 
| 14 |  |  | \ref{chap:sarch}. | 
| 15 | adcroft | 1.4 |  | 
| 16 |  |  | \section{Where to find information} | 
| 17 |  |  | \label{sect:whereToFindInfo} | 
| 18 | edhill | 1.30 | \begin{rawhtml} | 
| 19 |  |  | <!-- CMIREDIR:whereToFindInfo: --> | 
| 20 |  |  | \end{rawhtml} | 
| 21 | adcroft | 1.4 |  | 
| 22 | molod | 1.37 | There is a web-archived support mailing list for the model that | 
| 23 | edhill | 1.15 | you can email at \texttt{MITgcm-support@mitgcm.org} or browse at: | 
| 24 |  |  | \begin{rawhtml} <A href=http://mitgcm.org/mailman/listinfo/mitgcm-support/ target="idontexist"> \end{rawhtml} | 
| 25 |  |  | \begin{verbatim} | 
| 26 |  |  | http://mitgcm.org/mailman/listinfo/mitgcm-support/ | 
| 27 |  |  | http://mitgcm.org/pipermail/mitgcm-support/ | 
| 28 |  |  | \end{verbatim} | 
| 29 |  |  | \begin{rawhtml} </A> \end{rawhtml} | 
| 30 | adcroft | 1.4 |  | 
| 31 |  |  | \section{Obtaining the code} | 
| 32 |  |  | \label{sect:obtainingCode} | 
| 33 | edhill | 1.30 | \begin{rawhtml} | 
| 34 |  |  | <!-- CMIREDIR:obtainingCode: --> | 
| 35 |  |  | \end{rawhtml} | 
| 36 | adcroft | 1.1 |  | 
| 37 | cnh | 1.7 | MITgcm can be downloaded from our system by following | 
| 38 |  |  | the instructions below. As a courtesy we ask that you send e-mail to us at | 
| 39 | edhill | 1.14 | \begin{rawhtml} <A href=mailto:MITgcm-support@mitgcm.org> \end{rawhtml} | 
| 40 |  |  | MITgcm-support@mitgcm.org | 
| 41 | cnh | 1.7 | \begin{rawhtml} </A> \end{rawhtml} | 
| 42 |  |  | to enable us to keep track of who's using the model and in what application. | 
| 43 |  |  | You can download the model two ways: | 
| 44 |  |  |  | 
| 45 |  |  | \begin{enumerate} | 
| 46 | cnh | 1.9 | \item Using CVS software. CVS is a freely available source code management | 
| 47 | cnh | 1.7 | tool. To use CVS you need to have the software installed. Many systems | 
| 48 |  |  | come with CVS pre-installed, otherwise good places to look for | 
| 49 |  |  | the software for a particular platform are | 
| 50 |  |  | \begin{rawhtml} <A href=http://www.cvshome.org/ target="idontexist"> \end{rawhtml} | 
| 51 |  |  | cvshome.org | 
| 52 |  |  | \begin{rawhtml} </A> \end{rawhtml} | 
| 53 |  |  | and | 
| 54 |  |  | \begin{rawhtml} <A href=http://www.wincvs.org/ target="idontexist"> \end{rawhtml} | 
| 55 |  |  | wincvs.org | 
| 56 |  |  | \begin{rawhtml} </A> \end{rawhtml} | 
| 57 |  |  | . | 
| 58 |  |  |  | 
| 59 |  |  | \item Using a tar file. This method is simple and does not | 
| 60 |  |  | require any special software. However, this method does not | 
| 61 |  |  | provide easy support for maintenance updates. | 
| 62 |  |  |  | 
| 63 |  |  | \end{enumerate} | 
| 64 |  |  |  | 
| 65 | cnh | 1.27 | \subsection{Method 1 - Checkout from CVS} | 
| 66 | edhill | 1.19 | \label{sect:cvs_checkout} | 
| 67 |  |  |  | 
| 68 | adcroft | 1.1 | If CVS is available on your system, we strongly encourage you to use it. CVS | 
| 69 |  |  | provides an efficient and elegant way of organizing your code and keeping | 
| 70 |  |  | track of your changes. If CVS is not available on your machine, you can also | 
| 71 |  |  | download a tar file. | 
| 72 |  |  |  | 
| 73 | edhill | 1.15 | Before you can use CVS, the following environment variable(s) should | 
| 74 |  |  | be set within your shell.  For a csh or tcsh shell, put the following | 
| 75 |  |  | \begin{verbatim} | 
| 76 |  |  | % setenv CVSROOT :pserver:cvsanon@mitgcm.org:/u/gcmpack | 
| 77 |  |  | \end{verbatim} | 
| 78 | edhill | 1.31 | in your \texttt{.cshrc} or \texttt{.tcshrc} file.  For bash or sh | 
| 79 |  |  | shells, put: | 
| 80 | adcroft | 1.1 | \begin{verbatim} | 
| 81 | edhill | 1.15 | % export CVSROOT=':pserver:cvsanon@mitgcm.org:/u/gcmpack' | 
| 82 | adcroft | 1.6 | \end{verbatim} | 
| 83 | edhill | 1.20 | in your \texttt{.profile} or \texttt{.bashrc} file. | 
| 84 | adcroft | 1.6 |  | 
| 85 | edhill | 1.15 |  | 
| 86 |  |  | To get MITgcm through CVS, first register with the MITgcm CVS server | 
| 87 |  |  | using command: | 
| 88 | adcroft | 1.6 | \begin{verbatim} | 
| 89 | adcroft | 1.1 | % cvs login ( CVS password: cvsanon ) | 
| 90 |  |  | \end{verbatim} | 
| 91 | edhill | 1.15 | You only need to do a ``cvs login'' once. | 
| 92 | adcroft | 1.1 |  | 
| 93 | edhill | 1.15 | To obtain the latest sources type: | 
| 94 |  |  | \begin{verbatim} | 
| 95 |  |  | % cvs co MITgcm | 
| 96 |  |  | \end{verbatim} | 
| 97 |  |  | or to get a specific release type: | 
| 98 | adcroft | 1.1 | \begin{verbatim} | 
| 99 | edhill | 1.16 | % cvs co -P -r checkpoint52i_post  MITgcm | 
| 100 | adcroft | 1.1 | \end{verbatim} | 
| 101 | edhill | 1.15 | The MITgcm web site contains further directions concerning the source | 
| 102 |  |  | code and CVS.  It also contains a web interface to our CVS archive so | 
| 103 |  |  | that one may easily view the state of files, revisions, and other | 
| 104 |  |  | development milestones: | 
| 105 | jmc | 1.40 | %\begin{rawhtml} <A href="http://mitgcm.org/download" target="idontexist"> \end{rawhtml} | 
| 106 |  |  | \begin{rawhtml} <A href="http://mitgcm.org/viewvc/MITgcm/MITgcm/" target="idontexist"> \end{rawhtml} | 
| 107 | edhill | 1.15 | \begin{verbatim} | 
| 108 | edhill | 1.17 | http://mitgcm.org/source_code.html | 
| 109 | edhill | 1.15 | \end{verbatim} | 
| 110 |  |  | \begin{rawhtml} </A> \end{rawhtml} | 
| 111 | adcroft | 1.1 |  | 
| 112 | edhill | 1.19 | As a convenience, the MITgcm CVS server contains aliases which are | 
| 113 |  |  | named subsets of the codebase.  These aliases can be especially | 
| 114 |  |  | helpful when used over slow internet connections or on machines with | 
| 115 |  |  | restricted storage space.  Table \ref{tab:cvsModules} contains a list | 
| 116 |  |  | of CVS aliases | 
| 117 |  |  | \begin{table}[htb] | 
| 118 |  |  | \centering | 
| 119 |  |  | \begin{tabular}[htb]{|lp{3.25in}|}\hline | 
| 120 |  |  | \textbf{Alias Name}    &  \textbf{Information (directories) Contained}  \\\hline | 
| 121 |  |  | \texttt{MITgcm\_code}  &  Only the source code -- none of the verification examples.  \\ | 
| 122 |  |  | \texttt{MITgcm\_verif\_basic} | 
| 123 |  |  | &  Source code plus a small set of the verification examples | 
| 124 |  |  | (\texttt{global\_ocean.90x40x15}, \texttt{aim.5l\_cs}, \texttt{hs94.128x64x5}, | 
| 125 |  |  | \texttt{front\_relax}, and \texttt{plume\_on\_slope}).  \\ | 
| 126 |  |  | \texttt{MITgcm\_verif\_atmos}  &  Source code plus all of the atmospheric examples.  \\ | 
| 127 |  |  | \texttt{MITgcm\_verif\_ocean}  &  Source code plus all of the oceanic examples.  \\ | 
| 128 |  |  | \texttt{MITgcm\_verif\_all}    &  Source code plus all of the | 
| 129 |  |  | verification examples. \\\hline | 
| 130 |  |  | \end{tabular} | 
| 131 |  |  | \caption{MITgcm CVS Modules} | 
| 132 |  |  | \label{tab:cvsModules} | 
| 133 |  |  | \end{table} | 
| 134 | edhill | 1.15 |  | 
| 135 | edhill | 1.31 | The checkout process creates a directory called \texttt{MITgcm}. If | 
| 136 |  |  | the directory \texttt{MITgcm} exists this command updates your code | 
| 137 | edhill | 1.15 | based on the repository. Each directory in the source tree contains a | 
| 138 | edhill | 1.31 | directory \texttt{CVS}. This information is required by CVS to keep | 
| 139 | edhill | 1.15 | track of your file versions with respect to the repository. Don't edit | 
| 140 | edhill | 1.31 | the files in \texttt{CVS}!  You can also use CVS to download code | 
| 141 | edhill | 1.15 | updates.  More extensive information on using CVS for maintaining | 
| 142 |  |  | MITgcm code can be found | 
| 143 | edhill | 1.34 | \begin{rawhtml} <A href="http://mitgcm.org/usingcvstoget.html" target="idontexist"> \end{rawhtml} | 
| 144 | cnh | 1.7 | here | 
| 145 |  |  | \begin{rawhtml} </A> \end{rawhtml} | 
| 146 |  |  | . | 
| 147 | edhill | 1.19 | It is important to note that the CVS aliases in Table | 
| 148 |  |  | \ref{tab:cvsModules} cannot be used in conjunction with the CVS | 
| 149 |  |  | \texttt{-d DIRNAME} option.  However, the \texttt{MITgcm} directories | 
| 150 |  |  | they create can be changed to a different name following the check-out: | 
| 151 |  |  | \begin{verbatim} | 
| 152 |  |  | %  cvs co MITgcm_verif_basic | 
| 153 |  |  | %  mv MITgcm MITgcm_verif_basic | 
| 154 |  |  | \end{verbatim} | 
| 155 | cnh | 1.7 |  | 
| 156 | edhill | 1.19 | \subsubsection{Upgrading from an earlier version} | 
| 157 | adcroft | 1.12 |  | 
| 158 |  |  | If you already have an earlier version of the code you can ``upgrade'' | 
| 159 |  |  | your copy instead of downloading the entire repository again. First, | 
| 160 |  |  | ``cd'' (change directory) to the top of your working copy: | 
| 161 |  |  | \begin{verbatim} | 
| 162 |  |  | % cd MITgcm | 
| 163 |  |  | \end{verbatim} | 
| 164 | edhill | 1.15 | and then issue the cvs update command such as: | 
| 165 | adcroft | 1.12 | \begin{verbatim} | 
| 166 | edhill | 1.16 | % cvs -q update -r checkpoint52i_post -d -P | 
| 167 | adcroft | 1.12 | \end{verbatim} | 
| 168 | edhill | 1.16 | This will update the ``tag'' to ``checkpoint52i\_post'', add any new | 
| 169 | adcroft | 1.12 | directories (-d) and remove any empty directories (-P). The -q option | 
| 170 |  |  | means be quiet which will reduce the number of messages you'll see in | 
| 171 |  |  | the terminal. If you have modified the code prior to upgrading, CVS | 
| 172 |  |  | will try to merge your changes with the upgrades. If there is a | 
| 173 |  |  | conflict between your modifications and the upgrade, it will report | 
| 174 |  |  | that file with a ``C'' in front, e.g.: | 
| 175 |  |  | \begin{verbatim} | 
| 176 |  |  | C model/src/ini_parms.F | 
| 177 |  |  | \end{verbatim} | 
| 178 |  |  | If the list of conflicts scrolled off the screen, you can re-issue the | 
| 179 |  |  | cvs update command and it will report the conflicts. Conflicts are | 
| 180 | edhill | 1.15 | indicated in the code by the delimites ``$<<<<<<<$'', ``======='' and | 
| 181 |  |  | ``$>>>>>>>$''. For example, | 
| 182 | edhill | 1.17 | {\small | 
| 183 | adcroft | 1.12 | \begin{verbatim} | 
| 184 |  |  | <<<<<<< ini_parms.F | 
| 185 |  |  | & bottomDragLinear,myOwnBottomDragCoefficient, | 
| 186 |  |  | ======= | 
| 187 |  |  | & bottomDragLinear,bottomDragQuadratic, | 
| 188 |  |  | >>>>>>> 1.18 | 
| 189 |  |  | \end{verbatim} | 
| 190 | edhill | 1.17 | } | 
| 191 | adcroft | 1.12 | means that you added ``myOwnBottomDragCoefficient'' to a namelist at | 
| 192 |  |  | the same time and place that we added ``bottomDragQuadratic''. You | 
| 193 |  |  | need to resolve this conflict and in this case the line should be | 
| 194 |  |  | changed to: | 
| 195 | edhill | 1.17 | {\small | 
| 196 | adcroft | 1.12 | \begin{verbatim} | 
| 197 |  |  | & bottomDragLinear,bottomDragQuadratic,myOwnBottomDragCoefficient, | 
| 198 |  |  | \end{verbatim} | 
| 199 | edhill | 1.17 | } | 
| 200 | edhill | 1.15 | and the lines with the delimiters ($<<<<<<$,======,$>>>>>>$) be deleted. | 
| 201 | adcroft | 1.12 | Unless you are making modifications which exactly parallel | 
| 202 |  |  | developments we make, these types of conflicts should be rare. | 
| 203 |  |  |  | 
| 204 |  |  | \paragraph*{Upgrading to the current pre-release version} | 
| 205 |  |  |  | 
| 206 |  |  | We don't make a ``release'' for every little patch and bug fix in | 
| 207 |  |  | order to keep the frequency of upgrades to a minimum. However, if you | 
| 208 |  |  | have run into a problem for which ``we have already fixed in the | 
| 209 |  |  | latest code'' and we haven't made a ``tag'' or ``release'' since that | 
| 210 |  |  | patch then you'll need to get the latest code: | 
| 211 |  |  | \begin{verbatim} | 
| 212 |  |  | % cvs -q update -A -d -P | 
| 213 |  |  | \end{verbatim} | 
| 214 |  |  | Unlike, the ``check-out'' and ``update'' procedures above, there is no | 
| 215 |  |  | ``tag'' or release name. The -A tells CVS to upgrade to the | 
| 216 |  |  | very latest version. As a rule, we don't recommend this since you | 
| 217 |  |  | might upgrade while we are in the processes of checking in the code so | 
| 218 |  |  | that you may only have part of a patch. Using this method of updating | 
| 219 |  |  | also means we can't tell what version of the code you are working | 
| 220 |  |  | with. So please be sure you understand what you're doing. | 
| 221 |  |  |  | 
| 222 | molod | 1.37 | \subsection{Method 2 - Tar file download} | 
| 223 |  |  | \label{sect:conventionalDownload} | 
| 224 |  |  |  | 
| 225 |  |  | If you do not have CVS on your system, you can download the model as a | 
| 226 |  |  | tar file from the web site at: | 
| 227 | jmc | 1.40 | \begin{rawhtml} <A href=http://mitgcm.org/download/ target="idontexist"> \end{rawhtml} | 
| 228 | molod | 1.37 | \begin{verbatim} | 
| 229 |  |  | http://mitgcm.org/download/ | 
| 230 |  |  | \end{verbatim} | 
| 231 |  |  | \begin{rawhtml} </A> \end{rawhtml} | 
| 232 |  |  | The tar file still contains CVS information which we urge you not to | 
| 233 |  |  | delete; even if you do not use CVS yourself the information can help | 
| 234 |  |  | us if you should need to send us your copy of the code.  If a recent | 
| 235 |  |  | tar file does not exist, then please contact the developers through | 
| 236 |  |  | the | 
| 237 |  |  | \begin{rawhtml} <A href="mailto:MITgcm-support@mitgcm.org"> \end{rawhtml} | 
| 238 |  |  | MITgcm-support@mitgcm.org | 
| 239 |  |  | \begin{rawhtml} </A> \end{rawhtml} | 
| 240 |  |  | mailing list. | 
| 241 |  |  |  | 
| 242 | adcroft | 1.4 | \section{Model and directory structure} | 
| 243 | edhill | 1.30 | \begin{rawhtml} | 
| 244 |  |  | <!-- CMIREDIR:directory_structure: --> | 
| 245 |  |  | \end{rawhtml} | 
| 246 | adcroft | 1.1 |  | 
| 247 | adcroft | 1.12 | The ``numerical'' model is contained within a execution environment | 
| 248 |  |  | support wrapper. This wrapper is designed to provide a general | 
| 249 |  |  | framework for grid-point models. MITgcmUV is a specific numerical | 
| 250 |  |  | model that uses the framework. Under this structure the model is split | 
| 251 |  |  | into execution environment support code and conventional numerical | 
| 252 |  |  | model code. The execution environment support code is held under the | 
| 253 | edhill | 1.31 | \texttt{eesupp} directory. The grid point model code is held under the | 
| 254 |  |  | \texttt{model} directory. Code execution actually starts in the | 
| 255 |  |  | \texttt{eesupp} routines and not in the \texttt{model} routines. For | 
| 256 |  |  | this reason the top-level \texttt{MAIN.F} is in the | 
| 257 |  |  | \texttt{eesupp/src} directory. In general, end-users should not need | 
| 258 | edhill | 1.17 | to worry about this level. The top-level routine for the numerical | 
| 259 | edhill | 1.31 | part of the code is in \texttt{model/src/THE\_MODEL\_MAIN.F}. Here is | 
| 260 | edhill | 1.17 | a brief description of the directory structure of the model under the | 
| 261 |  |  | root tree (a detailed description is given in section 3: Code | 
| 262 |  |  | structure). | 
| 263 | adcroft | 1.1 |  | 
| 264 |  |  | \begin{itemize} | 
| 265 |  |  |  | 
| 266 | edhill | 1.31 | \item \texttt{doc}: contains brief documentation notes. | 
| 267 |  |  |  | 
| 268 |  |  | \item \texttt{eesupp}: contains the execution environment source code. | 
| 269 |  |  | Also subdivided into two subdirectories \texttt{inc} and | 
| 270 |  |  | \texttt{src}. | 
| 271 | edhill | 1.17 |  | 
| 272 | edhill | 1.31 | \item \texttt{model}: this directory contains the main source code. | 
| 273 |  |  | Also subdivided into two subdirectories \texttt{inc} and | 
| 274 |  |  | \texttt{src}. | 
| 275 | edhill | 1.17 |  | 
| 276 | edhill | 1.31 | \item \texttt{pkg}: contains the source code for the packages. Each | 
| 277 |  |  | package corresponds to a subdirectory. For example, \texttt{gmredi} | 
| 278 | edhill | 1.17 | contains the code related to the Gent-McWilliams/Redi scheme, | 
| 279 | edhill | 1.31 | \texttt{aim} the code relative to the atmospheric intermediate | 
| 280 | molod | 1.37 | physics. The packages are described in detail in chapter \ref{chap.packagesI}. | 
| 281 | edhill | 1.17 |  | 
| 282 | edhill | 1.31 | \item \texttt{tools}: this directory contains various useful tools. | 
| 283 |  |  | For example, \texttt{genmake2} is a script written in csh (C-shell) | 
| 284 | edhill | 1.17 | that should be used to generate your makefile. The directory | 
| 285 | edhill | 1.31 | \texttt{adjoint} contains the makefile specific to the Tangent | 
| 286 | edhill | 1.17 | linear and Adjoint Compiler (TAMC) that generates the adjoint code. | 
| 287 | molod | 1.37 | The latter is described in detail in part \ref{chap.ecco}. | 
| 288 |  |  | This directory also contains the subdirectory build\_options, which | 
| 289 |  |  | contains the `optfiles' with the compiler options for the different | 
| 290 |  |  | compilers and machines that can run MITgcm. | 
| 291 | edhill | 1.17 |  | 
| 292 | edhill | 1.31 | \item \texttt{utils}: this directory contains various utilities. The | 
| 293 |  |  | subdirectory \texttt{knudsen2} contains code and a makefile that | 
| 294 | edhill | 1.17 | compute coefficients of the polynomial approximation to the knudsen | 
| 295 |  |  | formula for an ocean nonlinear equation of state. The | 
| 296 | edhill | 1.31 | \texttt{matlab} subdirectory contains matlab scripts for reading | 
| 297 |  |  | model output directly into matlab. \texttt{scripts} contains C-shell | 
| 298 | edhill | 1.17 | post-processing scripts for joining processor-based and tiled-based | 
| 299 | molod | 1.37 | model output. The subdirectory exch2 contains the code needed for | 
| 300 |  |  | the exch2 package to work with different combinations of domain | 
| 301 |  |  | decompositions. | 
| 302 | edhill | 1.17 |  | 
| 303 | edhill | 1.31 | \item \texttt{verification}: this directory contains the model | 
| 304 | edhill | 1.17 | examples. See section \ref{sect:modelExamples}. | 
| 305 | adcroft | 1.1 |  | 
| 306 | molod | 1.37 | \item \texttt{jobs}: contains sample job scripts for running MITgcm. | 
| 307 |  |  |  | 
| 308 |  |  | \item \texttt{lsopt}: Line search code used for optimization. | 
| 309 |  |  |  | 
| 310 |  |  | \item \texttt{optim}: Interface between MITgcm and line search code. | 
| 311 |  |  |  | 
| 312 | adcroft | 1.1 | \end{itemize} | 
| 313 |  |  |  | 
| 314 | cnh | 1.26 | \section[Building MITgcm]{Building the code} | 
| 315 | adcroft | 1.4 | \label{sect:buildingCode} | 
| 316 | edhill | 1.30 | \begin{rawhtml} | 
| 317 |  |  | <!-- CMIREDIR:buildingCode: --> | 
| 318 |  |  | \end{rawhtml} | 
| 319 | adcroft | 1.4 |  | 
| 320 | edhill | 1.31 | To compile the code, we use the \texttt{make} program. This uses a | 
| 321 |  |  | file (\texttt{Makefile}) that allows us to pre-process source files, | 
| 322 |  |  | specify compiler and optimization options and also figures out any | 
| 323 |  |  | file dependencies. We supply a script (\texttt{genmake2}), described | 
| 324 |  |  | in section \ref{sect:genmake}, that automatically creates the | 
| 325 |  |  | \texttt{Makefile} for you. You then need to build the dependencies and | 
| 326 | edhill | 1.16 | compile the code. | 
| 327 | adcroft | 1.4 |  | 
| 328 | edhill | 1.31 | As an example, assume that you want to build and run experiment | 
| 329 |  |  | \texttt{verification/exp2}. The are multiple ways and places to | 
| 330 | edhill | 1.16 | actually do this but here let's build the code in | 
| 331 | edhill | 1.31 | \texttt{verification/exp2/build}: | 
| 332 | adcroft | 1.4 | \begin{verbatim} | 
| 333 | edhill | 1.31 | % cd verification/exp2/build | 
| 334 | adcroft | 1.4 | \end{verbatim} | 
| 335 | edhill | 1.31 | First, build the \texttt{Makefile}: | 
| 336 | adcroft | 1.4 | \begin{verbatim} | 
| 337 | edhill | 1.16 | % ../../../tools/genmake2 -mods=../code | 
| 338 | adcroft | 1.4 | \end{verbatim} | 
| 339 | edhill | 1.31 | The command line option tells \texttt{genmake} to override model source | 
| 340 |  |  | code with any files in the directory \texttt{../code/}. | 
| 341 | adcroft | 1.4 |  | 
| 342 | edhill | 1.31 | On many systems, the \texttt{genmake2} program will be able to | 
| 343 | edhill | 1.16 | automatically recognize the hardware, find compilers and other tools | 
| 344 | edhill | 1.31 | within the user's path (``\texttt{echo \$PATH}''), and then choose an | 
| 345 | edhill | 1.29 | appropriate set of options from the files (``optfiles'') contained in | 
| 346 | edhill | 1.31 | the \texttt{tools/build\_options} directory.  Under some | 
| 347 |  |  | circumstances, a user may have to create a new ``optfile'' in order to | 
| 348 |  |  | specify the exact combination of compiler, compiler flags, libraries, | 
| 349 |  |  | and other options necessary to build a particular configuration of | 
| 350 |  |  | MITgcm.  In such cases, it is generally helpful to read the existing | 
| 351 |  |  | ``optfiles'' and mimic their syntax. | 
| 352 | edhill | 1.16 |  | 
| 353 |  |  | Through the MITgcm-support list, the MITgcm developers are willing to | 
| 354 |  |  | provide help writing or modifing ``optfiles''.  And we encourage users | 
| 355 |  |  | to post new ``optfiles'' (particularly ones for new machines or | 
| 356 | edhill | 1.17 | architectures) to the | 
| 357 | edhill | 1.34 | \begin{rawhtml} <A href="mailto:MITgcm-support@mitgcm.org"> \end{rawhtml} | 
| 358 | edhill | 1.17 | MITgcm-support@mitgcm.org | 
| 359 |  |  | \begin{rawhtml} </A> \end{rawhtml} | 
| 360 |  |  | list. | 
| 361 | edhill | 1.16 |  | 
| 362 | edhill | 1.31 | To specify an optfile to \texttt{genmake2}, the syntax is: | 
| 363 | adcroft | 1.4 | \begin{verbatim} | 
| 364 | edhill | 1.16 | % ../../../tools/genmake2 -mods=../code -of /path/to/optfile | 
| 365 | adcroft | 1.4 | \end{verbatim} | 
| 366 |  |  |  | 
| 367 | edhill | 1.31 | Once a \texttt{Makefile} has been generated, we create the | 
| 368 |  |  | dependencies with the command: | 
| 369 | adcroft | 1.4 | \begin{verbatim} | 
| 370 |  |  | % make depend | 
| 371 |  |  | \end{verbatim} | 
| 372 | edhill | 1.31 | This modifies the \texttt{Makefile} by attaching a (usually, long) | 
| 373 |  |  | list of files upon which other files depend. The purpose of this is to | 
| 374 |  |  | reduce re-compilation if and when you start to modify the code. The | 
| 375 |  |  | {\tt make depend} command also creates links from the model source to | 
| 376 |  |  | this directory.  It is important to note that the {\tt make depend} | 
| 377 |  |  | stage will occasionally produce warnings or errors since the | 
| 378 |  |  | dependency parsing tool is unable to find all of the necessary header | 
| 379 |  |  | files (\textit{eg.}  \texttt{netcdf.inc}).  In these circumstances, it | 
| 380 |  |  | is usually OK to ignore the warnings/errors and proceed to the next | 
| 381 |  |  | step. | 
| 382 | adcroft | 1.1 |  | 
| 383 | edhill | 1.31 | Next one can compile the code using: | 
| 384 | adcroft | 1.4 | \begin{verbatim} | 
| 385 |  |  | % make | 
| 386 |  |  | \end{verbatim} | 
| 387 | edhill | 1.31 | The {\tt make} command creates an executable called \texttt{mitgcmuv}. | 
| 388 | edhill | 1.16 | Additional make ``targets'' are defined within the makefile to aid in | 
| 389 | edhill | 1.31 | the production of adjoint and other versions of MITgcm.  On SMP | 
| 390 |  |  | (shared multi-processor) systems, the build process can often be sped | 
| 391 |  |  | up appreciably using the command: | 
| 392 |  |  | \begin{verbatim} | 
| 393 |  |  | % make -j 2 | 
| 394 |  |  | \end{verbatim} | 
| 395 |  |  | where the ``2'' can be replaced with a number that corresponds to the | 
| 396 |  |  | number of CPUs available. | 
| 397 | adcroft | 1.4 |  | 
| 398 |  |  | Now you are ready to run the model. General instructions for doing so are | 
| 399 | edhill | 1.31 | given in section \ref{sect:runModel}. Here, we can run the model by | 
| 400 |  |  | first creating links to all the input files: | 
| 401 |  |  | \begin{verbatim} | 
| 402 |  |  | ln -s ../input/* . | 
| 403 |  |  | \end{verbatim} | 
| 404 |  |  | and then calling the executable with: | 
| 405 | adcroft | 1.4 | \begin{verbatim} | 
| 406 |  |  | ./mitgcmuv > output.txt | 
| 407 |  |  | \end{verbatim} | 
| 408 | edhill | 1.31 | where we are re-directing the stream of text output to the file | 
| 409 |  |  | \texttt{output.txt}. | 
| 410 | adcroft | 1.4 |  | 
| 411 | molod | 1.35 | \subsection{Building/compiling the code elsewhere} | 
| 412 |  |  |  | 
| 413 |  |  | In the example above (section \ref{sect:buildingCode}) we built the | 
| 414 |  |  | executable in the {\em input} directory of the experiment for | 
| 415 |  |  | convenience. You can also configure and compile the code in other | 
| 416 |  |  | locations, for example on a scratch disk with out having to copy the | 
| 417 |  |  | entire source tree. The only requirement to do so is you have {\tt | 
| 418 |  |  | genmake2} in your path or you know the absolute path to {\tt | 
| 419 |  |  | genmake2}. | 
| 420 |  |  |  | 
| 421 |  |  | The following sections outline some possible methods of organizing | 
| 422 |  |  | your source and data. | 
| 423 |  |  |  | 
| 424 |  |  | \subsubsection{Building from the {\em ../code directory}} | 
| 425 |  |  |  | 
| 426 |  |  | This is just as simple as building in the {\em input/} directory: | 
| 427 |  |  | \begin{verbatim} | 
| 428 |  |  | % cd verification/exp2/code | 
| 429 |  |  | % ../../../tools/genmake2 | 
| 430 |  |  | % make depend | 
| 431 |  |  | % make | 
| 432 |  |  | \end{verbatim} | 
| 433 |  |  | However, to run the model the executable ({\em mitgcmuv}) and input | 
| 434 |  |  | files must be in the same place. If you only have one calculation to make: | 
| 435 |  |  | \begin{verbatim} | 
| 436 |  |  | % cd ../input | 
| 437 |  |  | % cp ../code/mitgcmuv ./ | 
| 438 |  |  | % ./mitgcmuv > output.txt | 
| 439 |  |  | \end{verbatim} | 
| 440 |  |  | or if you will be making multiple runs with the same executable: | 
| 441 |  |  | \begin{verbatim} | 
| 442 |  |  | % cd ../ | 
| 443 |  |  | % cp -r input run1 | 
| 444 |  |  | % cp code/mitgcmuv run1 | 
| 445 |  |  | % cd run1 | 
| 446 |  |  | % ./mitgcmuv > output.txt | 
| 447 |  |  | \end{verbatim} | 
| 448 |  |  |  | 
| 449 |  |  | \subsubsection{Building from a new directory} | 
| 450 |  |  |  | 
| 451 |  |  | Since the {\em input} directory contains input files it is often more | 
| 452 |  |  | useful to keep {\em input} pristine and build in a new directory | 
| 453 |  |  | within {\em verification/exp2/}: | 
| 454 |  |  | \begin{verbatim} | 
| 455 |  |  | % cd verification/exp2 | 
| 456 |  |  | % mkdir build | 
| 457 |  |  | % cd build | 
| 458 |  |  | % ../../../tools/genmake2 -mods=../code | 
| 459 |  |  | % make depend | 
| 460 |  |  | % make | 
| 461 |  |  | \end{verbatim} | 
| 462 |  |  | This builds the code exactly as before but this time you need to copy | 
| 463 |  |  | either the executable or the input files or both in order to run the | 
| 464 |  |  | model. For example, | 
| 465 |  |  | \begin{verbatim} | 
| 466 |  |  | % cp ../input/* ./ | 
| 467 |  |  | % ./mitgcmuv > output.txt | 
| 468 |  |  | \end{verbatim} | 
| 469 |  |  | or if you tend to make multiple runs with the same executable then | 
| 470 |  |  | running in a new directory each time might be more appropriate: | 
| 471 |  |  | \begin{verbatim} | 
| 472 |  |  | % cd ../ | 
| 473 |  |  | % mkdir run1 | 
| 474 |  |  | % cp build/mitgcmuv run1/ | 
| 475 |  |  | % cp input/* run1/ | 
| 476 |  |  | % cd run1 | 
| 477 |  |  | % ./mitgcmuv > output.txt | 
| 478 |  |  | \end{verbatim} | 
| 479 |  |  |  | 
| 480 |  |  | \subsubsection{Building on a scratch disk} | 
| 481 |  |  |  | 
| 482 |  |  | Model object files and output data can use up large amounts of disk | 
| 483 |  |  | space so it is often the case that you will be operating on a large | 
| 484 |  |  | scratch disk. Assuming the model source is in {\em ~/MITgcm} then the | 
| 485 |  |  | following commands will build the model in {\em /scratch/exp2-run1}: | 
| 486 |  |  | \begin{verbatim} | 
| 487 |  |  | % cd /scratch/exp2-run1 | 
| 488 |  |  | % ~/MITgcm/tools/genmake2 -rootdir=~/MITgcm \ | 
| 489 |  |  | -mods=~/MITgcm/verification/exp2/code | 
| 490 |  |  | % make depend | 
| 491 |  |  | % make | 
| 492 |  |  | \end{verbatim} | 
| 493 |  |  | To run the model here, you'll need the input files: | 
| 494 |  |  | \begin{verbatim} | 
| 495 |  |  | % cp ~/MITgcm/verification/exp2/input/* ./ | 
| 496 |  |  | % ./mitgcmuv > output.txt | 
| 497 |  |  | \end{verbatim} | 
| 498 |  |  |  | 
| 499 |  |  | As before, you could build in one directory and make multiple runs of | 
| 500 |  |  | the one experiment: | 
| 501 |  |  | \begin{verbatim} | 
| 502 |  |  | % cd /scratch/exp2 | 
| 503 |  |  | % mkdir build | 
| 504 |  |  | % cd build | 
| 505 |  |  | % ~/MITgcm/tools/genmake2 -rootdir=~/MITgcm \ | 
| 506 |  |  | -mods=~/MITgcm/verification/exp2/code | 
| 507 |  |  | % make depend | 
| 508 |  |  | % make | 
| 509 |  |  | % cd ../ | 
| 510 |  |  | % cp -r ~/MITgcm/verification/exp2/input run2 | 
| 511 |  |  | % cd run2 | 
| 512 |  |  | % ./mitgcmuv > output.txt | 
| 513 |  |  | \end{verbatim} | 
| 514 |  |  |  | 
| 515 |  |  |  | 
| 516 |  |  | \subsection{Using \texttt{genmake2}} | 
| 517 |  |  | \label{sect:genmake} | 
| 518 |  |  |  | 
| 519 |  |  | To compile the code, first use the program \texttt{genmake2} (located | 
| 520 |  |  | in the \texttt{tools} directory) to generate a Makefile. | 
| 521 |  |  | \texttt{genmake2} is a shell script written to work with all | 
| 522 |  |  | ``sh''--compatible shells including bash v1, bash v2, and Bourne. | 
| 523 |  |  | Internally, \texttt{genmake2} determines the locations of needed | 
| 524 |  |  | files, the compiler, compiler options, libraries, and Unix tools.  It | 
| 525 |  |  | relies upon a number of ``optfiles'' located in the | 
| 526 |  |  | \texttt{tools/build\_options} directory. | 
| 527 |  |  |  | 
| 528 |  |  | The purpose of the optfiles is to provide all the compilation options | 
| 529 |  |  | for particular ``platforms'' (where ``platform'' roughly means the | 
| 530 |  |  | combination of the hardware and the compiler) and code configurations. | 
| 531 |  |  | Given the combinations of possible compilers and library dependencies | 
| 532 |  |  | ({\it eg.}  MPI and NetCDF) there may be numerous optfiles available | 
| 533 |  |  | for a single machine.  The naming scheme for the majority of the | 
| 534 |  |  | optfiles shipped with the code is | 
| 535 |  |  | \begin{center} | 
| 536 |  |  | {\bf OS\_HARDWARE\_COMPILER } | 
| 537 |  |  | \end{center} | 
| 538 |  |  | where | 
| 539 |  |  | \begin{description} | 
| 540 |  |  | \item[OS] is the name of the operating system (generally the | 
| 541 |  |  | lower-case output of the {\tt 'uname'} command) | 
| 542 |  |  | \item[HARDWARE] is a string that describes the CPU type and | 
| 543 |  |  | corresponds to output from the  {\tt 'uname -m'} command: | 
| 544 |  |  | \begin{description} | 
| 545 |  |  | \item[ia32] is for ``x86'' machines such as i386, i486, i586, i686, | 
| 546 |  |  | and athlon | 
| 547 |  |  | \item[ia64] is for Intel IA64 systems (eg. Itanium, Itanium2) | 
| 548 |  |  | \item[amd64] is AMD x86\_64 systems | 
| 549 |  |  | \item[ppc] is for Mac PowerPC systems | 
| 550 |  |  | \end{description} | 
| 551 |  |  | \item[COMPILER] is the compiler name (generally, the name of the | 
| 552 |  |  | FORTRAN executable) | 
| 553 |  |  | \end{description} | 
| 554 |  |  |  | 
| 555 |  |  | In many cases, the default optfiles are sufficient and will result in | 
| 556 |  |  | usable Makefiles.  However, for some machines or code configurations, | 
| 557 |  |  | new ``optfiles'' must be written. To create a new optfile, it is | 
| 558 |  |  | generally best to start with one of the defaults and modify it to suit | 
| 559 |  |  | your needs.  Like \texttt{genmake2}, the optfiles are all written | 
| 560 |  |  | using a simple ``sh''--compatible syntax.  While nearly all variables | 
| 561 |  |  | used within \texttt{genmake2} may be specified in the optfiles, the | 
| 562 |  |  | critical ones that should be defined are: | 
| 563 |  |  |  | 
| 564 |  |  | \begin{description} | 
| 565 |  |  | \item[FC] the FORTRAN compiler (executable) to use | 
| 566 |  |  | \item[DEFINES] the command-line DEFINE options passed to the compiler | 
| 567 |  |  | \item[CPP] the C pre-processor to use | 
| 568 |  |  | \item[NOOPTFLAGS] options flags for special files that should not be | 
| 569 |  |  | optimized | 
| 570 |  |  | \end{description} | 
| 571 |  |  |  | 
| 572 |  |  | For example, the optfile for a typical Red Hat Linux machine (``ia32'' | 
| 573 |  |  | architecture) using the GCC (g77) compiler is | 
| 574 |  |  | \begin{verbatim} | 
| 575 |  |  | FC=g77 | 
| 576 |  |  | DEFINES='-D_BYTESWAPIO -DWORDLENGTH=4' | 
| 577 |  |  | CPP='cpp  -traditional -P' | 
| 578 |  |  | NOOPTFLAGS='-O0' | 
| 579 |  |  | #  For IEEE, use the "-ffloat-store" option | 
| 580 |  |  | if test "x$IEEE" = x ; then | 
| 581 |  |  | FFLAGS='-Wimplicit -Wunused -Wuninitialized' | 
| 582 |  |  | FOPTIM='-O3 -malign-double -funroll-loops' | 
| 583 |  |  | else | 
| 584 |  |  | FFLAGS='-Wimplicit -Wunused -ffloat-store' | 
| 585 |  |  | FOPTIM='-O0 -malign-double' | 
| 586 |  |  | fi | 
| 587 |  |  | \end{verbatim} | 
| 588 |  |  |  | 
| 589 |  |  | If you write an optfile for an unrepresented machine or compiler, you | 
| 590 |  |  | are strongly encouraged to submit the optfile to the MITgcm project | 
| 591 |  |  | for inclusion.  Please send the file to the | 
| 592 |  |  | \begin{rawhtml} <A href="mail-to:MITgcm-support@mitgcm.org"> \end{rawhtml} | 
| 593 |  |  | \begin{center} | 
| 594 |  |  | MITgcm-support@mitgcm.org | 
| 595 |  |  | \end{center} | 
| 596 |  |  | \begin{rawhtml} </A> \end{rawhtml} | 
| 597 |  |  | mailing list. | 
| 598 |  |  |  | 
| 599 |  |  | In addition to the optfiles, \texttt{genmake2} supports a number of | 
| 600 |  |  | helpful command-line options.  A complete list of these options can be | 
| 601 |  |  | obtained from: | 
| 602 |  |  | \begin{verbatim} | 
| 603 |  |  | % genmake2 -h | 
| 604 |  |  | \end{verbatim} | 
| 605 |  |  |  | 
| 606 |  |  | The most important command-line options are: | 
| 607 |  |  | \begin{description} | 
| 608 |  |  |  | 
| 609 |  |  | \item[\texttt{--optfile=/PATH/FILENAME}] specifies the optfile that | 
| 610 |  |  | should be used for a particular build. | 
| 611 |  |  |  | 
| 612 |  |  | If no "optfile" is specified (either through the command line or the | 
| 613 |  |  | MITGCM\_OPTFILE environment variable), genmake2 will try to make a | 
| 614 |  |  | reasonable guess from the list provided in {\em | 
| 615 |  |  | tools/build\_options}.  The method used for making this guess is | 
| 616 |  |  | to first determine the combination of operating system and hardware | 
| 617 |  |  | (eg. "linux\_ia32") and then find a working FORTRAN compiler within | 
| 618 |  |  | the user's path.  When these three items have been identified, | 
| 619 |  |  | genmake2 will try to find an optfile that has a matching name. | 
| 620 |  |  |  | 
| 621 |  |  | \item[\texttt{--pdefault='PKG1 PKG2 PKG3 ...'}] specifies the default | 
| 622 |  |  | set of packages to be used.  The normal order of precedence for | 
| 623 |  |  | packages is as follows: | 
| 624 |  |  | \begin{enumerate} | 
| 625 |  |  | \item If available, the command line (\texttt{--pdefault}) settings | 
| 626 |  |  | over-rule any others. | 
| 627 |  |  |  | 
| 628 |  |  | \item Next, \texttt{genmake2} will look for a file named | 
| 629 |  |  | ``\texttt{packages.conf}'' in the local directory or in any of the | 
| 630 |  |  | directories specified with the \texttt{--mods} option. | 
| 631 |  |  |  | 
| 632 |  |  | \item Finally, if neither of the above are available, | 
| 633 |  |  | \texttt{genmake2} will use the \texttt{/pkg/pkg\_default} file. | 
| 634 |  |  | \end{enumerate} | 
| 635 |  |  |  | 
| 636 |  |  | \item[\texttt{--pdepend=/PATH/FILENAME}] specifies the dependency file | 
| 637 |  |  | used for packages. | 
| 638 |  |  |  | 
| 639 |  |  | If not specified, the default dependency file {\em pkg/pkg\_depend} | 
| 640 |  |  | is used.  The syntax for this file is parsed on a line-by-line basis | 
| 641 |  |  | where each line containes either a comment ("\#") or a simple | 
| 642 |  |  | "PKGNAME1 (+|-)PKGNAME2" pairwise rule where the "+" or "-" symbol | 
| 643 |  |  | specifies a "must be used with" or a "must not be used with" | 
| 644 |  |  | relationship, respectively.  If no rule is specified, then it is | 
| 645 |  |  | assumed that the two packages are compatible and will function | 
| 646 |  |  | either with or without each other. | 
| 647 |  |  |  | 
| 648 |  |  | \item[\texttt{--adof=/path/to/file}] specifies the "adjoint" or | 
| 649 |  |  | automatic differentiation options file to be used.  The file is | 
| 650 |  |  | analogous to the ``optfile'' defined above but it specifies | 
| 651 |  |  | information for the AD build process. | 
| 652 |  |  |  | 
| 653 |  |  | The default file is located in {\em | 
| 654 |  |  | tools/adjoint\_options/adjoint\_default} and it defines the "TAF" | 
| 655 |  |  | and "TAMC" compilers.  An alternate version is also available at | 
| 656 |  |  | {\em tools/adjoint\_options/adjoint\_staf} that selects the newer | 
| 657 |  |  | "STAF" compiler.  As with any compilers, it is helpful to have their | 
| 658 |  |  | directories listed in your {\tt \$PATH} environment variable. | 
| 659 |  |  |  | 
| 660 |  |  | \item[\texttt{--mods='DIR1 DIR2 DIR3 ...'}] specifies a list of | 
| 661 |  |  | directories containing ``modifications''.  These directories contain | 
| 662 |  |  | files with names that may (or may not) exist in the main MITgcm | 
| 663 |  |  | source tree but will be overridden by any identically-named sources | 
| 664 |  |  | within the ``MODS'' directories. | 
| 665 |  |  |  | 
| 666 |  |  | The order of precedence for this "name-hiding" is as follows: | 
| 667 |  |  | \begin{itemize} | 
| 668 |  |  | \item ``MODS'' directories (in the order given) | 
| 669 |  |  | \item Packages either explicitly specified or provided by default | 
| 670 |  |  | (in the order given) | 
| 671 |  |  | \item Packages included due to package dependencies (in the order | 
| 672 |  |  | that that package dependencies are parsed) | 
| 673 |  |  | \item The "standard dirs" (which may have been specified by the | 
| 674 |  |  | ``-standarddirs'' option) | 
| 675 |  |  | \end{itemize} | 
| 676 |  |  |  | 
| 677 |  |  | \item[\texttt{--mpi}] This option enables certain MPI features (using | 
| 678 |  |  | CPP \texttt{\#define}s) within the code and is necessary for MPI | 
| 679 |  |  | builds (see Section \ref{sect:mpi-build}). | 
| 680 |  |  |  | 
| 681 |  |  | \item[\texttt{--make=/path/to/gmake}] Due to the poor handling of | 
| 682 |  |  | soft-links and other bugs common with the \texttt{make} versions | 
| 683 |  |  | provided by commercial Unix vendors, GNU \texttt{make} (sometimes | 
| 684 |  |  | called \texttt{gmake}) should be preferred.  This option provides a | 
| 685 |  |  | means for specifying the make executable to be used. | 
| 686 |  |  |  | 
| 687 |  |  | \item[\texttt{--bash=/path/to/sh}] On some (usually older UNIX) | 
| 688 |  |  | machines, the ``bash'' shell is unavailable.  To run on these | 
| 689 |  |  | systems, \texttt{genmake2} can be invoked using an ``sh'' (that is, | 
| 690 |  |  | a Bourne, POSIX, or compatible) shell.  The syntax in these | 
| 691 |  |  | circumstances is: | 
| 692 |  |  | \begin{center} | 
| 693 |  |  | \texttt{\%  /bin/sh genmake2 -bash=/bin/sh [...options...]} | 
| 694 |  |  | \end{center} | 
| 695 |  |  | where \texttt{/bin/sh} can be replaced with the full path and name | 
| 696 |  |  | of the desired shell. | 
| 697 |  |  |  | 
| 698 |  |  | \end{description} | 
| 699 |  |  |  | 
| 700 |  |  |  | 
| 701 |  |  | \subsection{Building with MPI} | 
| 702 |  |  | \label{sect:mpi-build} | 
| 703 |  |  |  | 
| 704 |  |  | Building MITgcm to use MPI libraries can be complicated due to the | 
| 705 |  |  | variety of different MPI implementations available, their dependencies | 
| 706 |  |  | or interactions with different compilers, and their often ad-hoc | 
| 707 |  |  | locations within file systems.  For these reasons, its generally a | 
| 708 |  |  | good idea to start by finding and reading the documentation for your | 
| 709 |  |  | machine(s) and, if necessary, seeking help from your local systems | 
| 710 |  |  | administrator. | 
| 711 |  |  |  | 
| 712 |  |  | The steps for building MITgcm with MPI support are: | 
| 713 |  |  | \begin{enumerate} | 
| 714 |  |  |  | 
| 715 |  |  | \item Determine the locations of your MPI-enabled compiler and/or MPI | 
| 716 |  |  | libraries and put them into an options file as described in Section | 
| 717 |  |  | \ref{sect:genmake}.  One can start with one of the examples in: | 
| 718 |  |  | \begin{rawhtml} <A | 
| 719 | jmc | 1.40 | href="http://mitgcm.org/viewvc/MITgcm/MITgcm/tools/build_options/"> | 
| 720 | molod | 1.35 | \end{rawhtml} | 
| 721 |  |  | \begin{center} | 
| 722 |  |  | \texttt{MITgcm/tools/build\_options/} | 
| 723 |  |  | \end{center} | 
| 724 |  |  | \begin{rawhtml} </A> \end{rawhtml} | 
| 725 |  |  | such as \texttt{linux\_ia32\_g77+mpi\_cg01} or | 
| 726 |  |  | \texttt{linux\_ia64\_efc+mpi} and then edit it to suit the machine at | 
| 727 |  |  | hand.  You may need help from your user guide or local systems | 
| 728 |  |  | administrator to determine the exact location of the MPI libraries. | 
| 729 |  |  | If libraries are not installed, MPI implementations and related | 
| 730 |  |  | tools are available including: | 
| 731 |  |  | \begin{itemize} | 
| 732 |  |  | \item \begin{rawhtml} <A | 
| 733 |  |  | href="http://www-unix.mcs.anl.gov/mpi/mpich/"> | 
| 734 |  |  | \end{rawhtml} | 
| 735 |  |  | MPICH | 
| 736 |  |  | \begin{rawhtml} </A> \end{rawhtml} | 
| 737 |  |  |  | 
| 738 |  |  | \item \begin{rawhtml} <A | 
| 739 |  |  | href="http://www.lam-mpi.org/"> | 
| 740 |  |  | \end{rawhtml} | 
| 741 |  |  | LAM/MPI | 
| 742 |  |  | \begin{rawhtml} </A> \end{rawhtml} | 
| 743 |  |  |  | 
| 744 |  |  | \item \begin{rawhtml} <A | 
| 745 |  |  | href="http://www.osc.edu/~pw/mpiexec/"> | 
| 746 |  |  | \end{rawhtml} | 
| 747 |  |  | MPIexec | 
| 748 |  |  | \begin{rawhtml} </A> \end{rawhtml} | 
| 749 |  |  | \end{itemize} | 
| 750 |  |  |  | 
| 751 |  |  | \item Build the code with the \texttt{genmake2} \texttt{-mpi} option | 
| 752 |  |  | (see Section \ref{sect:genmake}) using commands such as: | 
| 753 |  |  | {\footnotesize \begin{verbatim} | 
| 754 |  |  | %  ../../../tools/genmake2 -mods=../code -mpi -of=YOUR_OPTFILE | 
| 755 |  |  | %  make depend | 
| 756 |  |  | %  make | 
| 757 |  |  | \end{verbatim} } | 
| 758 |  |  |  | 
| 759 |  |  | \item Run the code with the appropriate MPI ``run'' or ``exec'' | 
| 760 |  |  | program provided with your particular implementation of MPI. | 
| 761 |  |  | Typical MPI packages such as MPICH will use something like: | 
| 762 |  |  | \begin{verbatim} | 
| 763 |  |  | %  mpirun -np 4 -machinefile mf ./mitgcmuv | 
| 764 |  |  | \end{verbatim} | 
| 765 |  |  | Sightly more complicated scripts may be needed for many machines | 
| 766 |  |  | since execution of the code may be controlled by both the MPI | 
| 767 |  |  | library and a job scheduling and queueing system such as PBS, | 
| 768 |  |  | LoadLeveller, Condor, or any of a number of similar tools.  A few | 
| 769 |  |  | example scripts (those used for our \begin{rawhtml} <A | 
| 770 |  |  | href="http://mitgcm.org/testing.html"> \end{rawhtml}regular | 
| 771 |  |  | verification runs\begin{rawhtml} </A> \end{rawhtml}) are available | 
| 772 |  |  | at: | 
| 773 |  |  | \begin{rawhtml} <A | 
| 774 | jmc | 1.40 | href="http://mitgcm.org/viewvc/MITgcm/MITgcm_contrib/test_scripts/"> | 
| 775 | molod | 1.35 | \end{rawhtml} | 
| 776 |  |  | {\footnotesize \tt | 
| 777 | jmc | 1.40 | http://mitgcm.org/viewvc/MITgcm/MITgcm\_contrib/test\_scripts/ } | 
| 778 | molod | 1.35 | \begin{rawhtml} </A> \end{rawhtml} | 
| 779 |  |  |  | 
| 780 |  |  | \end{enumerate} | 
| 781 |  |  |  | 
| 782 |  |  | An example of the above process on the MITgcm cluster (``cg01'') using | 
| 783 |  |  | the GNU g77 compiler and the mpich MPI library is: | 
| 784 |  |  |  | 
| 785 |  |  | {\footnotesize \begin{verbatim} | 
| 786 |  |  | %  cd MITgcm/verification/exp5 | 
| 787 |  |  | %  mkdir build | 
| 788 |  |  | %  cd build | 
| 789 |  |  | %  ../../../tools/genmake2 -mpi -mods=../code \ | 
| 790 |  |  | -of=../../../tools/build_options/linux_ia32_g77+mpi_cg01 | 
| 791 |  |  | %  make depend | 
| 792 |  |  | %  make | 
| 793 |  |  | %  cd ../input | 
| 794 |  |  | %  /usr/local/pkg/mpi/mpi-1.2.4..8a-gm-1.5/g77/bin/mpirun.ch_gm \ | 
| 795 |  |  | -machinefile mf --gm-kill 5 -v -np 2  ../build/mitgcmuv | 
| 796 |  |  | \end{verbatim} } | 
| 797 | adcroft | 1.4 |  | 
| 798 | cnh | 1.26 | \section[Running MITgcm]{Running the model in prognostic mode} | 
| 799 | adcroft | 1.4 | \label{sect:runModel} | 
| 800 | edhill | 1.30 | \begin{rawhtml} | 
| 801 |  |  | <!-- CMIREDIR:runModel: --> | 
| 802 |  |  | \end{rawhtml} | 
| 803 | adcroft | 1.4 |  | 
| 804 | edhill | 1.31 | If compilation finished succesfully (section \ref{sect:buildingCode}) | 
| 805 | edhill | 1.23 | then an executable called \texttt{mitgcmuv} will now exist in the | 
| 806 |  |  | local directory. | 
| 807 | adcroft | 1.1 |  | 
| 808 | edhill | 1.29 | To run the model as a single process (\textit{ie.} not in parallel) | 
| 809 |  |  | simply type: | 
| 810 | adcroft | 1.1 | \begin{verbatim} | 
| 811 | adcroft | 1.4 | % ./mitgcmuv | 
| 812 | adcroft | 1.1 | \end{verbatim} | 
| 813 | adcroft | 1.4 | The ``./'' is a safe-guard to make sure you use the local executable | 
| 814 |  |  | in case you have others that exist in your path (surely odd if you | 
| 815 |  |  | do!). The above command will spew out many lines of text output to | 
| 816 |  |  | your screen.  This output contains details such as parameter values as | 
| 817 |  |  | well as diagnostics such as mean Kinetic energy, largest CFL number, | 
| 818 |  |  | etc. It is worth keeping this text output with the binary output so we | 
| 819 | edhill | 1.31 | normally re-direct the \texttt{stdout} stream as follows: | 
| 820 | adcroft | 1.1 | \begin{verbatim} | 
| 821 | adcroft | 1.4 | % ./mitgcmuv > output.txt | 
| 822 | adcroft | 1.1 | \end{verbatim} | 
| 823 | edhill | 1.29 | In the event that the model encounters an error and stops, it is very | 
| 824 |  |  | helpful to include the last few line of this \texttt{output.txt} file | 
| 825 |  |  | along with the (\texttt{stderr}) error message within any bug reports. | 
| 826 | adcroft | 1.1 |  | 
| 827 | edhill | 1.31 | For the example experiments in \texttt{verification}, an example of the | 
| 828 |  |  | output is kept in \texttt{results/output.txt} for comparison. You can | 
| 829 |  |  | compare your \texttt{output.txt} with the corresponding one for that | 
| 830 | edhill | 1.29 | experiment to check that the set-up works. | 
| 831 | adcroft | 1.1 |  | 
| 832 |  |  |  | 
| 833 |  |  |  | 
| 834 | adcroft | 1.4 | \subsection{Output files} | 
| 835 | adcroft | 1.1 |  | 
| 836 | edhill | 1.31 | The model produces various output files and, when using \texttt{mnc}, | 
| 837 |  |  | sometimes even directories.  Depending upon the I/O package(s) | 
| 838 |  |  | selected at compile time (either \texttt{mdsio} or \texttt{mnc} or | 
| 839 |  |  | both as determined by \texttt{code/packages.conf}) and the run-time | 
| 840 |  |  | flags set (in \texttt{input/data.pkg}), the following output may | 
| 841 |  |  | appear. | 
| 842 | edhill | 1.29 |  | 
| 843 |  |  |  | 
| 844 |  |  | \subsubsection{MDSIO output files} | 
| 845 |  |  |  | 
| 846 |  |  | The ``traditional'' output files are generated by the \texttt{mdsio} | 
| 847 |  |  | package.  At a minimum, the instantaneous ``state'' of the model is | 
| 848 |  |  | written out, which is made of the following files: | 
| 849 | adcroft | 1.1 |  | 
| 850 |  |  | \begin{itemize} | 
| 851 | edhill | 1.34 | \item \texttt{U.00000nIter} - zonal component of velocity field (m/s | 
| 852 |  |  | and positive eastward). | 
| 853 | adcroft | 1.1 |  | 
| 854 | edhill | 1.34 | \item \texttt{V.00000nIter} - meridional component of velocity field | 
| 855 |  |  | (m/s and positive northward). | 
| 856 | adcroft | 1.1 |  | 
| 857 | edhill | 1.34 | \item \texttt{W.00000nIter} - vertical component of velocity field | 
| 858 |  |  | (ocean: m/s and positive upward, atmosphere: Pa/s and positive | 
| 859 |  |  | towards increasing pressure i.e. downward). | 
| 860 | adcroft | 1.1 |  | 
| 861 | edhill | 1.34 | \item \texttt{T.00000nIter} - potential temperature (ocean: | 
| 862 |  |  | $^{\circ}\mathrm{C}$, atmosphere: $^{\circ}\mathrm{K}$). | 
| 863 | adcroft | 1.1 |  | 
| 864 | edhill | 1.34 | \item \texttt{S.00000nIter} - ocean: salinity (psu), atmosphere: water | 
| 865 |  |  | vapor (g/kg). | 
| 866 | adcroft | 1.1 |  | 
| 867 | edhill | 1.34 | \item \texttt{Eta.00000nIter} - ocean: surface elevation (m), | 
| 868 |  |  | atmosphere: surface pressure anomaly (Pa). | 
| 869 | adcroft | 1.1 | \end{itemize} | 
| 870 |  |  |  | 
| 871 | edhill | 1.31 | The chain \texttt{00000nIter} consists of ten figures that specify the | 
| 872 | edhill | 1.34 | iteration number at which the output is written out. For example, | 
| 873 |  |  | \texttt{U.0000000300} is the zonal velocity at iteration 300. | 
| 874 | adcroft | 1.1 |  | 
| 875 |  |  | In addition, a ``pickup'' or ``checkpoint'' file called: | 
| 876 |  |  |  | 
| 877 |  |  | \begin{itemize} | 
| 878 | edhill | 1.31 | \item \texttt{pickup.00000nIter} | 
| 879 | adcroft | 1.1 | \end{itemize} | 
| 880 |  |  |  | 
| 881 |  |  | is written out. This file represents the state of the model in a condensed | 
| 882 |  |  | form and is used for restarting the integration. If the C-D scheme is used, | 
| 883 |  |  | there is an additional ``pickup'' file: | 
| 884 |  |  |  | 
| 885 |  |  | \begin{itemize} | 
| 886 | edhill | 1.31 | \item \texttt{pickup\_cd.00000nIter} | 
| 887 | adcroft | 1.1 | \end{itemize} | 
| 888 |  |  |  | 
| 889 |  |  | containing the D-grid velocity data and that has to be written out as well | 
| 890 |  |  | in order to restart the integration. Rolling checkpoint files are the same | 
| 891 |  |  | as the pickup files but are named differently. Their name contain the chain | 
| 892 | edhill | 1.31 | \texttt{ckptA} or \texttt{ckptB} instead of \texttt{00000nIter}. They can be | 
| 893 | adcroft | 1.1 | used to restart the model but are overwritten every other time they are | 
| 894 |  |  | output to save disk space during long integrations. | 
| 895 |  |  |  | 
| 896 | edhill | 1.29 | \subsubsection{MNC output files} | 
| 897 |  |  |  | 
| 898 |  |  | Unlike the \texttt{mdsio} output, the \texttt{mnc}--generated output | 
| 899 |  |  | is usually (though not necessarily) placed within a subdirectory with | 
| 900 | molod | 1.38 | a name such as \texttt{mnc\_test\_\${DATE}\_\${SEQ}}. | 
| 901 | edhill | 1.29 |  | 
| 902 | adcroft | 1.4 | \subsection{Looking at the output} | 
| 903 | adcroft | 1.1 |  | 
| 904 | edhill | 1.29 | The ``traditional'' or mdsio model data are written according to a | 
| 905 |  |  | ``meta/data'' file format.  Each variable is associated with two files | 
| 906 | edhill | 1.31 | with suffix names \texttt{.data} and \texttt{.meta}. The | 
| 907 |  |  | \texttt{.data} file contains the data written in binary form | 
| 908 |  |  | (big\_endian by default). The \texttt{.meta} file is a ``header'' file | 
| 909 | edhill | 1.29 | that contains information about the size and the structure of the | 
| 910 | edhill | 1.31 | \texttt{.data} file. This way of organizing the output is particularly | 
| 911 | edhill | 1.29 | useful when running multi-processors calculations. The base version of | 
| 912 |  |  | the model includes a few matlab utilities to read output files written | 
| 913 |  |  | in this format. The matlab scripts are located in the directory | 
| 914 | edhill | 1.31 | \texttt{utils/matlab} under the root tree. The script \texttt{rdmds.m} | 
| 915 | edhill | 1.29 | reads the data. Look at the comments inside the script to see how to | 
| 916 |  |  | use it. | 
| 917 | adcroft | 1.1 |  | 
| 918 | adcroft | 1.4 | Some examples of reading and visualizing some output in {\em Matlab}: | 
| 919 |  |  | \begin{verbatim} | 
| 920 |  |  | % matlab | 
| 921 |  |  | >> H=rdmds('Depth'); | 
| 922 |  |  | >> contourf(H');colorbar; | 
| 923 |  |  | >> title('Depth of fluid as used by model'); | 
| 924 |  |  |  | 
| 925 |  |  | >> eta=rdmds('Eta',10); | 
| 926 |  |  | >> imagesc(eta');axis ij;colorbar; | 
| 927 |  |  | >> title('Surface height at iter=10'); | 
| 928 |  |  |  | 
| 929 |  |  | >> eta=rdmds('Eta',[0:10:100]); | 
| 930 |  |  | >> for n=1:11; imagesc(eta(:,:,n)');axis ij;colorbar;pause(.5);end | 
| 931 |  |  | \end{verbatim} | 
| 932 | adcroft | 1.1 |  | 
| 933 | edhill | 1.31 | Similar scripts for netCDF output (\texttt{rdmnc.m}) are available and | 
| 934 |  |  | they are described in Section \ref{sec:pkg:mnc}. | 
| 935 |  |  |  | 
| 936 | molod | 1.38 | The MNC output files are all in the ``self-describing'' netCDF | 
| 937 |  |  | format and can thus be browsed and/or plotted using tools such as: | 
| 938 |  |  | \begin{itemize} | 
| 939 |  |  | \item \texttt{ncdump} is a utility which is typically included | 
| 940 |  |  | with every netCDF install: | 
| 941 |  |  | \begin{rawhtml} <A href="http://www.unidata.ucar.edu/packages/netcdf/"> \end{rawhtml} | 
| 942 |  |  | \begin{verbatim} | 
| 943 |  |  | http://www.unidata.ucar.edu/packages/netcdf/ | 
| 944 |  |  | \end{verbatim} | 
| 945 |  |  | \begin{rawhtml} </A> \end{rawhtml} and it converts the netCDF | 
| 946 |  |  | binaries into formatted ASCII text files. | 
| 947 |  |  |  | 
| 948 |  |  | \item \texttt{ncview} utility is a very convenient and quick way | 
| 949 |  |  | to plot netCDF data and it runs on most OSes: | 
| 950 |  |  | \begin{rawhtml} <A href="http://meteora.ucsd.edu/~pierce/ncview_home_page.html"> \end{rawhtml} | 
| 951 |  |  | \begin{verbatim} | 
| 952 |  |  | http://meteora.ucsd.edu/~pierce/ncview_home_page.html | 
| 953 |  |  | \end{verbatim} | 
| 954 |  |  | \begin{rawhtml} </A> \end{rawhtml} | 
| 955 |  |  |  | 
| 956 |  |  | \item MatLAB(c) and other common post-processing environments provide | 
| 957 |  |  | various netCDF interfaces including: | 
| 958 |  |  | \begin{rawhtml} <A href="http://mexcdf.sourceforge.net/"> \end{rawhtml} | 
| 959 |  |  | \begin{verbatim} | 
| 960 |  |  | http://mexcdf.sourceforge.net/ | 
| 961 |  |  | \end{verbatim} | 
| 962 |  |  | \begin{rawhtml} </A> \end{rawhtml} | 
| 963 |  |  | \begin{rawhtml} <A href="http://woodshole.er.usgs.gov/staffpages/cdenham/public_html/MexCDF/nc4ml5.html"> \end{rawhtml} | 
| 964 |  |  | \begin{verbatim} | 
| 965 |  |  | http://woodshole.er.usgs.gov/staffpages/cdenham/public_html/MexCDF/nc4ml5.html | 
| 966 |  |  | \end{verbatim} | 
| 967 |  |  | \begin{rawhtml} </A> \end{rawhtml} | 
| 968 |  |  | \end{itemize} | 
| 969 |  |  |  |