Oprofile Linux 2.5 implementation

A special filesystem is set up for the oprofile device /dev/oprofile
Processor performance monitoring hardware set to cause interrupt when N events counted
Interrupt routine logs event (which process, instruction pointer, and event) into per cpu buffer
When a process exits all per cpu buffers are flushed into a larger system buffer
The daemon extract the data via reading the /dev/oprofile/buffer file and stores the data on a per executable basis in /var/lib/oprofile/samples

A special filesystem is set up for the oprofile device /dev/oprofile