Purpose of an Interrupt in Computer Organization

Interrupt is the mechanism by which modules like I/O or memory may interrupt the normal processing by CPU. It may be either clicking a mouse, dragging a cursor, printing a document etc the case where interrupt is getting generated.

Why we require Interrupt?
External devices are comparatively slower than CPU. So if there is no interrupt CPU would waste a lot of time waiting for external devices to match its speed with that of CPU. This decreases the efficiency of CPU. Hence, interrupt is required to eliminate these limitations.

With Interrupt:

  1. Suppose CPU instructs printer to print a certain document.
  2. While printer does its task, CPU engaged in executing other tasks.
  3. When printer is done with its given work, it tells CPU that it has done with its work.
    (The word ‘tells’ here is interrupt which sends one message that printer has done its work successfully.).


  • It increases the efficiency of CPU.
  • It decreases the waiting time of CPU.
  • Stops the wastage of instruction cycle.


  • CPU has to do a lot of work to handle interrupts, resume its previous execution of programs (in short, overhead required to handle the interrupt request.).

Attention reader! Don’t stop learning now. Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready.

My Personal Notes arrow_drop_up

Check out this Author's contributed articles.

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.