HP-MPI Version 2.3.1 for Linux Release Note

Table Of Contents
MPI_STDIO_OUTFILE and MPI_STDIO_ERRFILE. If these environment variables are
not set, /dev/null or NUL is used. In addition, these file specifications can include
the substrings %%, %h, %p, and %r, which are expanded to %, hostname, process
id, and rank number in MPI_COMM_WORLD. The files option causes the stdio options
p, r, and I to be ignored.
3.12 Using the -stdio=none Option
This option is equivalent to setting -stdio=files with MPI_STDIO_INFILE,
MPI_STDIO_OUTFILE and MPI_STDIO_ERRFILE all set to /dev/null or NUL.
3.13 Expanded Lightweight Instrumentation
This release extends HP-MPI lightweight instrumentation. Lightweight instrumentation
can be turned on by using either the -i option to mpirun or by setting the environment
variable MPI_INSTR.
HP-MPI lightweight instrumentation is now supported when using -ha:infra and
singletons. See “Singleton Launching” (page 22).
Instrumentation data now includes some information on messages sent to other MPI
worlds formed using MPI_Comm_accept(), MPI_Comm_connect(), or
MPI_Comm_join(). All off-world message data is accounted together using the
designation offw regardless of which off-world rank was involved in the
communication.
HP-MPI provides an API that enables users to access the lightweight instrumentation
data on a per-process basis before the application calling MPI_Finalize(). The
following declaration in C is necessary to access this functionality:
extern int hpmp_instrument_runtime(int reset)
A call to hpmp_instrument_runtime(0) populates the output file specified by the
-i option to mpirun or the MPI_INSTR environment variable with the statistics
available at the time of the call. Subsequent calls to hpmp_instrument_runtime()
or MPI_Finalize() will overwrite the contents of the specified file. A call to
hpmp_instrument_runtime(1) populates the file in the same way, but also resets
the statistics. If instrumentation is not being used, the call to
hpmp_instrument_runtime() has no effect.
3.14 The api option to MPI_INSTR
The api option to MPI_INSTR collects and prints detailed information about the MPI
Application Programming Interface (API). This option prints a new section in the
instrumentation output file for each MPI routine called by each rank. It contains the
MPI datatype and operation requested, along with message size, call counts, and timing
information.
The following is sample output from -I <file>:api on the example compute_pi.f:
3.12 Using the -stdio=none Option 23