cgdb - a gdb front end

You can debug a compute node process with gdb (the Gnu debugger). You do this by running cgdb on the service node, which forwards your gdb commands to the compute node, and displays the gdb response to you on the service node.

To use this feature, run yod with the -attach option. This will display the nodes the application has been allocated and will start a gdb debugging session on each compute node. yod will prompt you before it allows the application processes to procede to user code.

To start a debugging proxy on the service node which can attach to the debugger on a compute node, run cgdb with a physical node number from the yod display:

cgdb -n 24

Now you can enter gdb commands to debug the application process.

TotalView is a commerical graphical parallel debugger available from Etnus.