The MPE libraries that are distributed with mpich contain several
libraries for either logging information about the execution of each
MPI call to a file for later analysis or for tracing each call as it
occurs. These libraries may be accessed by simply providing a command
line argument to the compilation scripts; further, this needs only be
done when linking the program. For example, to create a log file of a
program such as cpi, the following steps are needed:
mpicc -c cpi.c
mpicc -o cpi -mpilog cpi.o
The log file will be written to a file with the name cpi.clog
or cpi.slog, depending on the value of the environment variable
MPE_LOG_FORMAT (clog is the default). The logfile can be
graphically displayed using the Jumpshot program, described in
Section Jumpshot
.
Another tool of interest is FPMPI [5]; this tool reports a summary of all MPI calls, providing information about message lenghts, communication patterns.
Jumpshot is a program for displaying logfiles produced using the MPE
logging libraries. Jumpshot is described in more detail in the
MPE Installation and User's manual [2]. Jumpshot
is a Java program and requires a functioning Java environment.
You can view a logfile such as
cpi.clog in the example above by using
logviewer cpi.clogThere are several available log formats and logviewer selects the version of jumpshot appropriate for a particular logfile. See the MPE manual, distributed along with this manual, for more details.