The Intel® MPI Library supports the GDB* and Allinea* DDT debuggers for debugging MPI applications. Before using a debugger, make sure you have the application debug symbols available. To generate debug symbols, compile your application with the -g option.
GDB*: The GNU Project Debugger
Use the following command to launch the GDB debugger with Intel® MPI Library:
$ mpirun -gdb -n 4 ./testc
You can work with the GDB debugger as you usually do with a single-process application. For details on how to work with parallel programs, see the GDB documentation at https://sourceware.org/gdb/onlinedocs/gdb/Inferiors-Connections-and-Programs.html#Inferiors-Connections-and-Programs.
You can also attach to a running job with:
$ mpirun -n 4 -gdba <pid>
Where <pid> is the process ID for the running MPI process.
You can debug MPI applications using the Allinea DDT* debugger. Intel does not provide support for this debugger, you should obtain the support from Allinea. According to the DDT documentation, DDT supports the Express Launch feature for the Intel MPI Library. You can debug your application as follows:
$ ddt mpirun -n <number-of-processes> [<other-mpirun-arguments>] <executable>
If you have issues with the DDT debugger, refer to the DDT documentation for help.