1
2.5kviews
What is the difference between the interrupt and polling?

discuss the parameters that distinguish between polling and interrupts..

1 Answer
0
88views

Difference Between Interrupt and Polling

Sr. No. Parameters Interrupt Polling
1 Mechanism Interrupt is considered a hardware mechanism. Pilling is a type of protocol.
2 Procedure Device notifies CPU that it needs CPU attention. CPU constantly checks device status whether it needs CPU's attention.
3 Service Provider Interrupt handler services the Device. CPU services the device.
4 Definition An interrupt is an event that is triggered by external components other than the CPU that alerts the CPU to perform a certain action. Polling is an asynchronous activity that samples the status of an external device by a client program.
5 Occurrences Interrupt can occur at any time. Polling occurs at regular intervals.
6 Indication The interrupt-request line indicates that a device needs service. The command-ready bit indicates the device needs service.
7 CPU Cycles CPU is disturbed only when a device needs servicing, which saves CPU cycles. CPU has to wait and check whether a device needs servicing which wastes lots of CPU cycles.
8 Efficiency Interrupt becomes inefficient when devices keep on interrupting the CPU repeatedly. Polling becomes inefficient when the CPU rarely finds a device ready for service.
9 Benefits Serves multiple devices, flexible, and efficient. Simple program, transmission reliability, and no need for additional chips.
10 Drawbacks More complex and time-consuming. Standby time and CPU cycle waste.
11 Example Let the bell ring then open the door to check who has come. Constantly keep on opening the door to check whether anybody has come.
Please log in to add an answer.