Unix Kernels
The Unix operation system has a kernel that handles the memory allocated to each program and manages the time when the programs run. The kernel also handles I/O (input and output). See Figure 1-1 on on page 8 of Unix Power Tools and also the discussion on pages 14-16 of Unix Power Tools.
Unix Processes
To see the processes running on a node, you can type: ps x or top. If you type top, you will see the processes change in real time, including the amount of memory allocated to each process and the percentage of the processor’s time allocated to each process. To quit the view from top you can type the letter q.