Parallel Programming Guide for HP-UX Systems

MPI
Running
Chapter 228
• MPI_TMPDIR
• MPI_WORKDIR
• TOTALVIEW
MPI_COMMD MPI_COMMD routes all off-host communication through daemons rather than
between processes. The MPI_COMMD syntax is as follows:
out_frags , in_frags
where
out_frags Specifies the number of 16Kbyte fragments available in shared memory for
outbound messages. Outbound messages are sent from processes on a given
host to processes on other hosts using the communication daemon.
The default value for out_frags is 64. Increasing the number of fragments
for applications with a large number of processes improves system
throughput.
in_frags Specifies the number of 16Kbyte fragments available in shared memory for
inbound messages. Inbound messages are sent from processes on one or
more hosts to processes on a given host using the communication daemon.
The default value for in_frags is 64. Increasing the number of fragments
for applications with a large number of processes improves system
throughput.
Refer to “Communicating using daemons” on page 50 for more information.
MPI_DLIB_FLAGS MPI_DLIB_FLAGS controls runtime options when you use the
diagnostics library. The MPI_DLIB_FLAGS syntax is a comma separated list as follows:
[ns,][h,][strict,][nmsg,][nwarn,][dump: prefix, ]
[dumpf: prefix ][x NUM ]
where
ns Disables message signature analysis.
h Disables default behavior in the diagnostic library that ignores user
specified error handlers. The default considers all errors to be fatal.
strict Enables MPI object-space corruption detection. Setting this option for
applications that make calls to routines in the MPI-2 standard may produce
false error messages.