HP-MPI User's Guide (11th Edition)

Debugging and troubleshooting
Debugging HP-MPI applications
Chapter 6202
To disable these checks or enable formatted or unformatted printing of
message data to a file, set the MPI_DLIB_FLAGS environment variable
options appropriately. See “MPI_DLIB_FLAGS” on page 146 for more
information.
To use the diagnostics library, specify the -ldmpi option to the build
scripts when you compile your application. This option is supported on
HP-UX, Linux, and Windows.
NOTE Using DLIB reduces application performance. Also, you cannot use DLIB
with instrumentation.
Enhanced debugging output
HP-MPI provides the stdio option to allow improved readability and
usefulness of MPI processes stdout and stderr. Options have been added
for handling standard input:
• Directed: Input is directed to a specific MPI process.
• Broadcast: Input is copied to the stdin of all processes.
• Ignore: Input is ignored.
The default behavior when using stdio is to ignore standard input.
Additional options are available to avoid confusing interleaving of
output:
• Line buffering, block buffering, or no buffering
• Prepending of processes ranks to their stdout and stderr
• Simplification of redundant output
For more information on stdio, refer to “External input and output” on
page 210.
This functionality is not provided when using -srun or -prun. See
--label option of srun in Appendix C for similar functionality.