COMPUTER ORGANIZATION AND ARCHITECTURE DESIGNING FOR PERFORMANCE NINTH EDITION
? Fetch: Read the next instruction from memory into the processor.
? Execute: Interpret the opcode and perform the indicated operation.
? Interrupt: If interrupts are enabled and an interrupt has occurred, save the
current process state and service the interrupt.
原文：http://www.cnblogs.com/yuanjiangw/p/6246690.html