In / proc / interrupts, I see that some interrupt numbers refer to IO-APIC-fasteoi, and some refer to the edge of IO-APIC.
What is the difference between the two types of interrupt controllers?
The difference is how interrupts fire. The -edge interrupt is triggered by the edge. This is the level of increase on the interrupt line. -Fasteoi interrupts are level interrupts that are triggered until an interrupt event is acknowledged in a programmable interrupt controller (PIC). EOI stands for End Of Interrupt. See also the Wikipedia article on EOI .