Difference between Interrupt and Polling Last Updated : 12 Jul, 2025 Comments Improve Suggest changes Like Article Like Report As modern computer systems grow increasingly complex, efficient communication between the CPU and peripheral devices becomes more critical. Devices like keyboards, mouse, printers, and network interfaces require timely interaction with the CPU to ensure smooth operation and user experience. Interrupts and polling represent two fundamental strategies for handling these interactions.What is Interrupt?Interrupt is a hardware mechanism in which, the device notices the CPU that it requires its attention. Interruptions can take place at any time. So when the CPU gets an interrupt signal through the indication interrupt-request line, the CPU stops the current process and responds to the interrupt by passing the control to the interrupt handler which services the device. AdvantagesSleep ModesParallel ProcessingDisadvantagesContext SwitchingInterrupt LatencyWhat is Polling?Polling is not a hardware mechanism, its a protocol in which CPU steadily checks whether the device needs attention. Whenever device tells process unit that it desires hardware processing, in polling process unit keeps asking the I/O device whether or not it desires CPU processing. The CPU ceaselessly check every and each device hooked up thereto for sleuthing whether or not any device desires hardware attention. Each device features a command-ready bit that indicates the standing of that device, i.e., whether or not it's some command to be read by hardware or not. If command bit is ready one, then it's some command to be read else if the bit is zero, then it's no commands.AdvantagesNo context switchingReduced interrupt overheadDisadvantagesInefficiencyIncreased Power Consumption Difference Between Interrupt and PollingInterruptPollingIn interrupt, the device notices the CPU that it requires its attention.Whereas, in polling, CPU steadily checks whether the device needs attention.An interrupt is not a protocol, its a hardware mechanism.Whereas it isn't a hardware mechanism, its a protocol.In interrupt, the device is serviced by interrupt handler.While in polling, the device is serviced by CPU.Interrupt can take place at any time.Whereas CPU steadily ballots the device at regular or proper interval.In interrupt, interrupt request line is used as indication for indicating that device requires servicing.While in polling, Command ready bit is used as indication for indicating that device requires servicing.In interrupts, processor is simply disturbed once any device interrupts it.On the opposite hand, in polling, processor waste countless processor cycles by repeatedly checking the command-ready little bit of each device.ConclusionInterrupts provide a more efficient and responsive method by allowing the CPU to perform tasks without constant monitoring, while polling, though simpler, can result in unnecessary CPU cycles being consumed. The choice between these mechanisms depends on the specific requirements of the system, such as the need for real-time processing, resource availability, and the complexity of the hardware. Comment More infoAdvertise with us Next Article What is an Operating System? M mks075 Follow Improve Article Tags : Operating Systems Difference Between Similar Reads Operating System Tutorial An Operating System(OS) is a software that manages and handles hardware and software resources of a computing device. Responsible for managing and controlling all the activities and sharing of computer resources among different running applications.A low-level Software that includes all the basic fu 4 min read OS BasicsWhat is an Operating System?An Operating System is a System software that manages all the resources of the computing device. Acts as an interface between the software and different parts of the computer or the computer hardware. Manages the overall resources and operations of the computer. 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The term was defined by David Patterson, Ga 15 min read PracticeLast Minute Notes – Operating SystemsAn Operating System (OS) is a system software that manages computer hardware, software resources, and provides common services for computer programs. It acts as an interface between the user and the computer hardware.Table of Content Types of Operating System (OS): ThreadsProcessCPU Scheduling Algor 15+ min read Operating System Interview QuestionsAn operating system acts as a GUI between the user and the computer system. In other words, an OS acts as an intermediary between the user and the computer hardware, managing resources such as memory, processing power, and input/output operations. Here some examples of popular operating systems incl 15+ min read Operating Systems - GATE CSE Previous Year QuestionsThe Operating System(OS) subject has high importance in GATE CSE exam because:large number of questions nearly 10-12% of the total asked significant weightage (9-11 marks) across multiple years which can also be seen in the below given table:YearApprox. Marks from OSNumber of QuestionsDifficulty Lev 2 min read Like