MPICH programs on SciClone
must be initiated via PBS using the pbsmpich
command rather than with mpirun. See the SciClone
User's Guide and pbsmpich
man page for complete details.
Due to configuration
and compilation problems, 64-bit versions of MPICH (v9a and v9b architectures)
are not available on SciClone under Solaris 9.
MPI has been faster and more stable than MPICH for most applications.
However, MPICH 1.2.5 exhibits better reliability on SMP nodes and scalability
to larger numbers of nodes than previous releases. Users are encouraged
to experiment with both LAM and MPICH to determine which works best
for a given application.
For proper operation,
the MPICH environment variable must be set in the user's ~/.cshrc file
to specify the desired variant (v8plusa/generic or v8plusb/ultra3cu).
$MPICH/bin should be in the user's search path, and $MPICH/man should
be included in the MANPATH. The file /usr/local/etc/templates/cshrc
contains the current recommended environment settings and includes options
for specifying which version of MPICH to use, and for switching between
MPICH and other MPI packages.
In addition, the P4_SOCKBUFSIZE
variable can be used to control the socket buffer size used for TCP
communication between processes, and the P4_GLOBMEMSIZE variable determines
the amount of shared memory set aside for intranode message passing.
These are set to reasonable defaults in /usr/local/etc/templates/cshrc,
but may need to be tuned for optimum performance in particular applications.