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作業系統
選擇國立政治大學 2025 · 考試 · 第 35 題
考科作業系統
In polling I/O, the main inefficiency comes from
- (A)the hardware controller when it notifies the CPU that the device is ready for service.
- (B)the basic polling operation that may be comprised of several CPU instructions.
- (C)polling when it is attempted repeatedly yet rarely finds a device ready for service.
- (D)the slow data transfer rate between a device and the host.