TOP usage
Command "top" can show how much resources each process uses.
Values
PID : Process ID
USER : Effective User ID
PR : Dynamic priority
NI : Nice value, also known as base priority
VIRT : Virtual Size of the task. This includes the size of process's executable binary, the data area and all the loaded shared libraries.
RES : The size of RAM currently consumed by the task. Swapped out portion of the task is not included.
SHR : Some memory areas could be shared between two or more task, this field reflects that shared areas. The example of shared area are shared library and SysV shared memory.
S : Task status
%CPU : The percentage of CPU time dedicated to run the task since the last top's screen update.
%MEM : The percentage of RAM currently consumed by the task.
TIME+ : The total CPU time the task has been used since it started. "+" sign means it is displayed with hundreth of a second granularity. By default, TIME/TIME+ doesn't account the CPU time used by the task's dead children.
COMMAND : Showing program names.
Source: http://www.linuxforums.org/articles/using-top-more-efficiently_89.html
