If the number of cycles spent busy - waiting is not excessive, then___________
A)interrupt driven i/o is more efficient than programmed i/o
B)programmed i/o is more efficient than interrupt driven i/o
C)both programmed and interrupt driven i/o are equally efficient
D)none of the mentioned

Question

Quizplus · Accepted Answer

Programmed I/O involves the CPU actively waiting (busy-waiting) for an I/O operation to complete, which can be efficient if the waiting time is short because it avoids the overhead associated with handling interrupts. In contrast, interrupt-driven I/O can introduce more overhead due to context switches and handling the interrupt, making programmed I/O more efficient when the busy-waiting time is not excessive.

If the Number of Cycles Spent Busy - Waiting Is