Topic summary
Local APIC
Extracted from the Wikipedia article Advanced Programmable Interrupt Controller.
Integrated local APICs
Local APICs (LAPICs) manage all external interrupts for some specific processor in an SMP system. In addition, they are able to accept and generate inter-processor interrupts (IPIs) between LAPICs. A single LAPIC may support up to 224 usable interrupt vectors from an I/O APIC. Vector numbers 0 to 31, out of 0 to 255, are reserved for exception handling by x86 processors.