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

Debugging and troubleshooting

Troubleshooting HP-MPI applications

Chapter 6 207

• Application binaries are accessible from the remote nodes. If the

binaries are located on a file share, use the UNC path (i.e.

\\node\share\path) to refer to the binary, as these may not be

properly mapped to a drive letter by the authenticated logon token.

• If a password is not already cached, use the -cache option for your

first run, or use the -pass option on all runs so the remote service

can authenticate with network resources. Without these options (or

using -nopass), remote processes will not have access to network

shares.

• If problems occur when trying to launch the remote processes, use

the mpidiag tool to verify remote authentication and access. Also

view the event logs to see if the service is issuing errors.

• Don't forget to quote any filenames or commands with paths that

have spaces. The default HP-MPI install location includes spaces:

"C:\Program Files (x86)\Hewlett-Packard\HP-MPI\bin ^

\mpirun"

"%MPI_ROOT%\bin\mpirun"

Running on HP-UX, Linux, and Windows

Run time problems originate from many sources and may include:

• Shared memory

• Message buffering

• Propagation of environment variables

• Fortran 90 programming features

• UNIX open file descriptors

• External input and output

Shared memory

When an MPI application starts, each MPI daemon attempts to allocate

a section of shared memory. This allocation can fail if the

system-imposed limit on the maximum number of allowed

shared-memory identifiers is exceeded or if the amount of available

physical memory is not sufficient to fill the request.