Over-run Policy - how a system handles a service which attempts to continue execution beyond its advertised deadline - e.g. the scheduler could terminate the service.
Packet Switched - a network protocol which allows links to be shared by multiple datagram or virtual circuit protocols and routes packets between end-points based upon their header information.
PC (program counter) - The Program Counter is normally a register used by a CPU to track the current or next address of main memory which contains a machine instruction to execute. (Note that a trace of the PC over time provides the definition of the thread of execution until a context switch occurs, if it does at all).
PCI - Peripheral Component Interconnect, see Shanley Text, page 771.
PCI Bus Probing - A process that allows a BIOS or OS software to find all PCI devices and functions on a given PCI bus using configuration space registers.