Developer Guide

  • 2021.2
  • 03/26/2021
  • Public Content


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

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
You can also attach to a running job with:
$ mpirun -n 4 -gdba <pid>
is the process ID for the running MPI process.

DDT* Debugger

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 <# of processes> [<other mpirun arguments>] <executable>
If you have issues with the DDT debugger, refer to the DDT documentation for help.

Product and Performance Information


Performance varies by use, configuration and other factors. Learn more at