Using the HPC Interactively
For debugging purposes, you can run programs interactively on the p575 or the Blue Gene. Here are the different ways:
P575/AIX via a reserved node
Use a LoadLeveler script like this example, which reserves one AIX p575 node (16 CPUs) for two hours:
Submit the above script, and keep an eye on progress with the llq command. Once the job starts, you will have an AIX node reserved for you, and a host.list file will be created so that you can use poe to run a program interactively on that node. Alternatively, you can use ssh -X to the node mentioned in the host.list file to run a GUI program. When you've finished using the node, use llcancel to kill the loadleveler job.
P575 via inter_8
Log in via ssh to the Blue Gene front end node and use mpirun interactively, for example: mpirun -np 32 helloworld.exe. If a Blue Gene block is available then it will be allocated and run interactively from the command line. Note that Blue Gene/L blocks are allocated in multiples of 32, 128, 512 1024 and 2048 CPUs. If you set the mpirun -verbose flag to 2 or higher, then you'll get voluminous information about the block allocation and startup on the Blue Gene.