661 |
computation is performed concurrently over as many processes and threads |
computation is performed concurrently over as many processes and threads |
662 |
as there are physical processors available to compute. |
as there are physical processors available to compute. |
663 |
|
|
664 |
|
An exception to the the use of {\em bi} and {\em bj} in loops arises in the |
665 |
|
exchange routines used when the exch2 package is used with the cubed |
666 |
|
sphere. In this case {\em bj} is generally set to 1 and the loop runs from |
667 |
|
1,{\em bi}. Within the loop {\em bi} is used to retrieve the tile number, |
668 |
|
which is then used to reference exchange parameters. |
669 |
|
|
670 |
The amount of computation that can be embedded |
The amount of computation that can be embedded |
671 |
a single loop over {\em bi} and {\em bj} varies for different parts of the |
a single loop over {\em bi} and {\em bj} varies for different parts of the |
672 |
MITgcm algorithm. Figure \ref{fig:bibj_extract} shows a code extract |
MITgcm algorithm. Figure \ref{fig:bibj_extract} shows a code extract |
935 |
File: {\em eesupp/inc/MAIN\_PDIRECTIVES2.h}\\ |
File: {\em eesupp/inc/MAIN\_PDIRECTIVES2.h}\\ |
936 |
File: {\em model/src/THE\_MODEL\_MAIN.F}\\ |
File: {\em model/src/THE\_MODEL\_MAIN.F}\\ |
937 |
File: {\em eesupp/src/MAIN.F}\\ |
File: {\em eesupp/src/MAIN.F}\\ |
938 |
File: {\em tools/genmake}\\ |
File: {\em tools/genmake2}\\ |
939 |
File: {\em eedata}\\ |
File: {\em eedata}\\ |
940 |
CPP: {\em TARGET\_SUN}\\ |
CPP: {\em TARGET\_SUN}\\ |
941 |
CPP: {\em TARGET\_DEC}\\ |
CPP: {\em TARGET\_DEC}\\ |
990 |
|
|
991 |
Additionally, compile time options are required to link in the |
Additionally, compile time options are required to link in the |
992 |
MPI libraries and header files. Examples of these options |
MPI libraries and header files. Examples of these options |
993 |
can be found in the {\em genmake} script that creates makefiles |
can be found in the {\em genmake2} script that creates makefiles |
994 |
for compilation. When this script is executed with the {bf -mpi} |
for compilation. When this script is executed with the {bf -mpi} |
995 |
flag it will generate a makefile that includes |
flag it will generate a makefile that includes |
996 |
paths for search for MPI head files and for linking in |
paths for search for MPI head files and for linking in |
1012 |
|
|
1013 |
\fbox{ |
\fbox{ |
1014 |
\begin{minipage}{4.75in} |
\begin{minipage}{4.75in} |
1015 |
File: {\em tools/genmake} |
File: {\em tools/genmake2} |
1016 |
\end{minipage} |
\end{minipage} |
1017 |
} \\ |
} \\ |
1018 |
\paragraph{\bf Execution} The mechanics of starting a program in |
\paragraph{\bf Execution} The mechanics of starting a program in |