--- manual/s_phys_pkgs/text/exch2.tex 2005/08/09 21:52:09 1.25 +++ manual/s_phys_pkgs/text/exch2.tex 2010/08/30 23:09:21 1.29 @@ -1,4 +1,4 @@ -% $Header: /home/ubuntu/mnt/e9_copy/manual/s_phys_pkgs/text/exch2.tex,v 1.25 2005/08/09 21:52:09 edhill Exp $ +% $Header: /home/ubuntu/mnt/e9_copy/manual/s_phys_pkgs/text/exch2.tex,v 1.29 2010/08/30 23:09:21 jmc Exp $ % $Name: $ %% * Introduction @@ -49,7 +49,7 @@ \begin{itemize} \item The exch2 package is included when \file{genmake2} is run. The easiest way to do this is to add the line \code{exch2} to the - \file{packages.conf} file -- see Section \ref{sect:buildingCode} + \file{packages.conf} file -- see Section \ref{sec:buildingCode} \sectiontitle{Building the code} for general details. @@ -81,7 +81,7 @@ and \ref{sec:exch2mpi} \sectiontitle{exch2, SIZE.h, and Multiprocessing}; a more general background on the subject relevant to MITgcm is presented in Section - \ref{sect:specifying_a_decomposition} + \ref{sec:specifying_a_decomposition} \sectiontitle{Specifying a decomposition}. \end{itemize} @@ -109,8 +109,8 @@ from the Matlab prompt (there are no parameters to pass) generates exch2 topology files \file{W2\_EXCH2\_TOPOLOGY.h} and \file{w2\_e2setup.F} in the working directory and displays a figure of -the topology via Matlab -- figures \ref{fig:6tile}, \ref{fig:12tile}, -and \ref{fig:24tile} are examples of the generated diagrams. The other +the topology via Matlab -- figures \ref{fig:6tile}, \ref{fig:18tile}, +and \ref{fig:48tile} are examples of the generated diagrams. The other m-files in the directory are subroutines called from \file{driver.m} and should not be run ``bare'' except for development purposes. \\ @@ -131,40 +131,49 @@ the tiles into which the subdomains are decomposed, and must evenly divide the integer assigned to \code{nr}, \code{nb} and \code{ng}. The result is a rectangular tiling of the subdomain. Figure -\ref{fig:24tile} shows one possible topology for a twenty-four-tile -cube, and figure \ref{fig:12tile} shows one for twelve tiles. \\ +\ref{fig:48tile} shows one possible topology for a twenty-four-tile +cube, and figure \ref{fig:6tile} shows one for six tiles. \\ \begin{figure} \begin{center} - \resizebox{4in}{!}{ - \includegraphics{part6/s24t_16x16.ps} + \resizebox{6in}{!}{ +% \includegraphics{s_phys_pkgs/figs/s24t_16x16.ps} + \includegraphics{s_phys_pkgs/figs/adjust_cs.ps} } \end{center} \caption{Plot of a cubed sphere topology with a 32$\times$192 domain divided into six 32$\times$32 subdomains, each of which is divided -into four tiles of width \code{tnx=16} and height \code{tny=16} for a -total of twenty-four tiles. The colored borders of the subdomains -represent the parameters \code{nr} (red), \code{nb} (blue), and -\code{ng} (green). } \label{fig:24tile} +into eight tiles of width \code{tnx=16} and height \code{tny=8} for a +total of forty-eight tiles. The colored borders of the subdomains +represent the parameters \code{nr} (red), \code{ng} (green), and +\code{nb} (blue). +This tiling is used in the example +verification/adjustment.cs-32x32x1/ +with the option (blanklist.txt) to remove the land-only 4 tiles +(11,12,13,14) which are filled in red on the plot. +} \label{fig:48tile} \end{figure} \begin{figure} \begin{center} - \resizebox{4in}{!}{ - \includegraphics{part6/s12t_16x32.ps} + \resizebox{6in}{!}{ +% \includegraphics{s_phys_pkgs/figs/s12t_16x32.ps} + \includegraphics{s_phys_pkgs/figs/polarcap.ps} } \end{center} -\caption{Plot of a cubed sphere topology with a 32$\times$192 domain -divided into six 32$\times$32 subdomains of two tiles each - (\code{tnx=16, tny=32}). -} \label{fig:12tile} +\caption{Plot of a non-square cubed sphere topology with +6 subdomains of different size (nr=90,ng=360,nb=90), +divided into one to four tiles each + (\code{tnx=90, tny=90}), resulting in a total of 18 tiles. +} \label{fig:18tile} \end{figure} \begin{figure} \begin{center} \resizebox{4in}{!}{ - \includegraphics{part6/s6t_32x32.ps} +% \includegraphics{s_phys_pkgs/figs/s6t_32x32.ps} + \includegraphics{s_phys_pkgs/figs/s6t_32x32.ps} } \end{center} \caption{Plot of a cubed sphere topology with a 32$\times$192 domain @@ -190,7 +199,7 @@ Once the topology configuration files are created, the Fortran \code{PARAMETER}s in \file{SIZE.h} must be configured to match. -Section \ref{sect:specifying_a_decomposition} \sectiontitle{Specifying +Section \ref{sec:specifying_a_decomposition} \sectiontitle{Specifying a decomposition} provides a general description of domain decomposition within MITgcm and its relation to \file{SIZE.h}. The current section specifies constraints that the exch2 package imposes @@ -231,17 +240,17 @@ processor. Such dummy tiles are \emph{not} listed in \file{blanklist.txt}. -The following is an example of \file{SIZE.h} for the twelve-tile -configuration illustrated in figure \ref{fig:12tile} running on one -processor: +The following is an example of \file{SIZE.h} for the six-tile +configuration illustrated in figure \ref{fig:6tile} +running on one processor: \begin{verbatim} PARAMETER ( - & sNx = 16, + & sNx = 32, & sNy = 32, & OLx = 2, & OLy = 2, - & nSx = 12, + & nSx = 6, & nSy = 1, & nPx = 1, & nPy = 1, @@ -250,16 +259,16 @@ & Nr = 5) \end{verbatim} -The following is an example for the twenty-four-tile topology in -figure \ref{fig:24tile} running on six processors: +The following is an example for the forty-eight-tile topology in +figure \ref{fig:48tile} running on six processors: \begin{verbatim} PARAMETER ( & sNx = 16, - & sNy = 16, + & sNy = 8, & OLx = 2, & OLy = 2, - & nSx = 4, + & nSx = 8, & nSy = 1, & nPx = 6, & nPy = 1, @@ -293,9 +302,9 @@ of tiles in the $x$ and $y$ global indices. For example, the default setup of six tiles (Fig. \ref{fig:6tile}) has \code{exch2\_domain\_nxt=6} and \code{exch2\_domain\_nyt=1}. A -topology of twenty-four square tiles, four per subdomain (as in figure -\ref{fig:24tile}), will have \code{exch2\_domain\_nxt=12} and -\code{exch2\_domain\_nyt=2}. Note that these parameters express the +topology of forty-eight tiles, eight per subdomain (as in figure +\ref{fig:48tile}), will have \code{exch2\_domain\_nxt=12} and +\code{exch2\_domain\_nyt=4}. Note that these parameters express the tile layout in order to allow global data files that are tile-layout-neutral. They have no bearing on the internal storage of the arrays. The tiles are stored internally in a range from \code{\varlink{bi}{bi}=(1:NTILES)} in the @@ -335,8 +344,8 @@ The array \varlink{exch2\_myFace}{exch2_myFace} contains the number of the subdomain of each tile, in a range \code{(1:6)} in the case of the standard cube topology and indicated by \textbf{\textsf{f}}$n$ in -figures \ref{fig:12tile} and -\ref{fig:24tile}. \varlink{exch2\_nNeighbours}{exch2_nNeighbours} +figures \ref{fig:6tile} and +\ref{fig:48tile}. \varlink{exch2\_nNeighbours}{exch2_nNeighbours} contains a count of the neighboring tiles each tile has, and sets the bounds for looping over neighboring tiles. \varlink{exch2\_tProc}{exch2_tProc} holds the process rank of each @@ -458,8 +467,8 @@ \varlink{exch2\_jthi\_c}{exch2_jthi_c} hold the location and index bounds of the edge segment of the neighbor tile \code{N}'s subdomain that gets exchanged with the local tile \code{T}. To take the example -of tile \code{T=2} in the twelve-tile topology -(Fig. \ref{fig:12tile}): \\ +of tile \code{T=2} in the forty-eight-tile topology +(Fig. \ref{fig:48tile}): \\ \begin{verbatim} exch2_itlo_c(4,2)=17 @@ -503,7 +512,7 @@ Most of the subroutines particular to exch2 handle the exchanges themselves and are of the same format as those described in -\ref{sect:cube_sphere_communication} \sectiontitle{Cube sphere +\ref{sec:cube_sphere_communication} \sectiontitle{Cube sphere communication}. Like the original routines, they are written as templates which the local Makefile converts from \code{RX} into \code{RL} and \code{RS} forms. \\ @@ -529,3 +538,10 @@ \code{EXCH2\_SEND\_RX1} and \code{EXCH2\_SEND\_RX2}, which do most of the work using the variables discussed above. \\ +\subsubsection{Experiments and tutorials that use exch2} +\label{sec:pkg:exch2:experiments} + +\begin{itemize} +\item{Held Suarez tutorial, in tutorial\_held\_suarez\_cs verification directory, +described in section \ref{sec:eg-hs} } +\end{itemize}