Pgdbg

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PGDBG is a powerful and simple tool for debugging both MPI-parallel and OpenMP thread-parallel Linux applications. It is included in the PGI compiler package and configured for OpenMP thread-parallel debugging.

PGI Debugger (pgdbg)

What is Pgdbg ?

For the most of the C, C++, or Fortran 77 codes one can use a regular GNU debugger such as GDB. However, the Fortran 90/95 programs are not handled very well by the GDB. The Portland Group has developed a debugger called pgdbg which is more suited for such codes. Pgdbg is provided in two modes: a graphical mode with the enabled X11 forwarding or a text mode. Pgdbg can be used to debug codes with MPI-parallel, OpenMP thread-parallel, or MPI-OpenMP hybrid instructions.

Preparing your application

Switch to PGI compiler

Load the appropriate PGI compiler. For example, for PGI 17.3:

[name@server ~]$ module load pgi/17.3

Compile your code

To be able to debug with pgdbg you first need to compile your code with debugging information enabled. With the pgdbg you do so by adding a debugging flag "-g":

[name@server ~]$ pgcc -g program.c -o program

Execute your code

Once your code is compiled with the proper options, you execute it:

[name@server ~]$ pgdbg program arg1 arg2

If you have set the X11 forwarding then the pgdbg will start in the graphical mode in a pop-up window. If you don't have X11 forwarding, you can run pgdbg in a text mode by adding an extra option "-text" :

[name@server ~]$ pgdbg -text program arg1 arg2

Message Passing Interface