--- manual/s_getstarted/text/getting_started.tex 2004/03/24 20:53:12 1.22 +++ manual/s_getstarted/text/getting_started.tex 2004/04/08 02:24:23 1.23 @@ -1,4 +1,4 @@ -% $Header: /home/ubuntu/mnt/e9_copy/manual/s_getstarted/text/getting_started.tex,v 1.22 2004/03/24 20:53:12 edhill Exp $ +% $Header: /home/ubuntu/mnt/e9_copy/manual/s_getstarted/text/getting_started.tex,v 1.23 2004/04/08 02:24:23 edhill Exp $ % $Name: $ %\section{Getting started} @@ -666,7 +666,6 @@ \end{verbatim} - \subsection{Using \textit{genmake2}} \label{sect:genmake} @@ -828,6 +827,10 @@ ``-standarddirs'' option) \end{itemize} +\item[\texttt{--mpi}] This option enables certain MPI features (using + CPP \texttt{\#define}s) within the code and is necessary for MPI + builds (see Section \ref{sect:mpi-build}). + \item[\texttt{--make=/path/to/gmake}] Due to the poor handling of soft-links and other bugs common with the \texttt{make} versions provided by commercial Unix vendors, GNU \texttt{make} (sometimes @@ -840,7 +843,7 @@ a Bourne, POSIX, or compatible) shell. The syntax in these circumstances is: \begin{center} - \texttt{/bin/sh genmake2 -bash=/bin/sh [...options...]} + \texttt{\% /bin/sh genmake2 -bash=/bin/sh [...options...]} \end{center} where \texttt{/bin/sh} can be replaced with the full path and name of the desired shell. @@ -848,13 +851,85 @@ \end{description} +\subsection{Building with MPI} +\label{sect:mpi-build} + +Building MITgcm to use MPI libraries can be complicated due to the +variety of different MPI implementations available, their dependencies +or interactions with different compilers, and their often ad-hoc +locations within file systems. For these reasons, its generally a +good idea to start by finding and reading the documentation for your +machine(s) and, if necessary, seeking help from your local systems +administrator. + +The steps for building MITgcm with MPI support are: +\begin{enumerate} + +\item Determine the locations of your MPI-enabled compiler and/or MPI + libraries and put them into an options file as described in Section + \ref{sect:genmake}. One can start with one of the examples in: + \begin{rawhtml} + \end{rawhtml} + \begin{center} + \texttt{MITgcm/tools/build\_options/} + \end{center} + \begin{rawhtml} \end{rawhtml} + such as \texttt{linux\_ia32\_g77+mpi\_cg01} or + \texttt{linux\_ia64\_efc+mpi} and then edit it to suit the machine at + hand. You may need help from your user guide or local systems + administrator to determine the exact location of the MPI libraries. + If libraries are not installed, MPI implementations and related + tools are available including: + \begin{itemize} + \item \begin{rawhtml} + \end{rawhtml} + MPICH + \begin{rawhtml} \end{rawhtml} + + \item \begin{rawhtml} + \end{rawhtml} + LAM/MPI + \begin{rawhtml} \end{rawhtml} + + \item \begin{rawhtml} + \end{rawhtml} + MPIexec + \begin{rawhtml} \end{rawhtml} + \end{itemize} + +\item Build the code with the \texttt{genmake2} \texttt{-mpi} option + (see Section \ref{sect:genmake}) using commands such as: +{\footnotesize \begin{verbatim} + % ../../../tools/genmake2 -mods=../code -mpi -of=YOUR_OPTFILE + % make depend + % make +\end{verbatim} } + +\item Run the code with the appropriate MPI ``run'' or ``exec'' + program provided with your particular implementation of MPI. + Typical MPI packages such as MPICH will use something like: +\begin{verbatim} + % mpirun -np 4 -machinefile mf ./mitgcmuv +\end{verbatim} + Sightly more complicated scripts may be needed for many machines + since execution of the code may be controlled by both the MPI + library and a job scheduling and queueing system such as PBS, + LoadLeveller, Condor, or any of a number of similar tools. + +\end{enumerate} + + \section{Running the model} \label{sect:runModel} -If compilation finished succesfuully (section \ref{sect:buildModel}) -then an executable called {\em mitgcmuv} will now exist in the local -directory. +If compilation finished succesfuully (section \ref{sect:buildingCode}) +then an executable called \texttt{mitgcmuv} will now exist in the +local directory. To run the model as a single process (ie. not in parallel) simply type: