D.6. VIRTUAL PARALLEL MACHINE | Parallel Computing on Heterogeneous Networks (Wiley Series on Parallel and Distributed Computing)

D.5. HOW TO START UP

Any workstation that may be used as a working place of the user is called a host workstation. The user may launch mpC applications only from host workstations.

To start working with the mpC environment, the user must have it installed on each computer of the NoC (see D.11 for installation guide).

The user should become an authorized user with the same name on each of the computers.

The user should make sure that on each computer of the NoC the user’s home directory has a Unix configuration file .rhosts with names of all computers of the NoC.

On each computer in the user’s home directory a file responsible for the shell environment (for example, .cshrc if C shell is used) should be modified to determine environmental variables WHICHMPI, MPIDIR (also LAMHOME when using LAM 6.3), MPCHOME, MPCTOPO, and MPCLOAD.

Note that sometimes different files should be modified for local and remote invocation of the shell. For example, if Bourne shell is used on a PC running Red Hat Linux 4.0, both .bashrc and bash_profile should be modified, one for local and the other for remote invocation.

There are a small number of restrictions depending on the value of WHICHMPI used:

When using LAM MPI, it may be necessary to determine the environmental variable TROLLIUSHOME setting it to the same value as MPIDIR.
When using LAM 6.3, the environmental variable LAMHOME must be set to the same value as MPIDIR.
When using LAM 6.3, it may be necessary to determine the environmental variable MPIFLAGS setting it to -lamd.
When using MPICH, the environmental variable MPCHOME must be set to the same value on all computers of the NoC. To ensure this, the user may need to use the Unix ln command to make the necessary hard or soft links.
When using MPICH, the environmental variable MPCLOAD must be set to the same value on all computers of the NoC. To ensure this, the user may need to use the Unix ln command to make necessary hard or soft links.
When using MPICH, the user should have write access to the directory $MPIDIR/bin/machines (equally, $MPIDIR/util/machines) on each host workstation.

On each computer the directories $MPCTOPO, $MPCTOPO/log, and $MPCLOAD must be created. Different users should not share the directories. Binary incompatible computers must not share any of these directories. The user must have write access to these directories.

On each computer the directories $MPIDIR/bin, $MPIDIR/lib, $MPCHOME/bin, $MPCHOME/lib, and $MPCLOAD should be added to PATH. To avoid name conflicts, the directory $MPCLOAD should be the first in the search path.

In addition, directories $MPIDIR/lib and $MPCHOME/lib should be added to the ld path (by modifying LD_LIBRARY_PATH for Solaris, LPATH for HP-UX and so on).