73 73 votes A device with data transfer rate $10$ KB/sec is connected to a CPU. Data is transferred byte-wise. Let the interrupt overhead be $4\mu$sec. The byte transfer time between the device interface register and CPU or memory is negligible. What is the minimum performance gain of operating the device under interrupt mode over operating it under program-controlled mode? $15$ $25$ $35$ $45$ CO & Architecture gatecse-2005 co-and-architecture interrupts + – Kathleen 29.6k views answer comment Share Follow Print See all 5 Comments 5 5 Comments reply Show 2 previous comments reboot commented Jan 14, 2021 reply Follow flag I think this question is a bit ambiguous. WHY? Because suppose data to be transferred is just 1B, then programmed i/o needs 1B of status register data transfer and then 1B of user data. Whereas interrupt doesn’t require any status bits. WHEREAS if we consider 10KB data then this 1B status register data seems negligible and can be ignored, and hence the answer changes. THEY should have mentioned the amount of data to be transferred. 0 0 replyShare Souvik33 commented Nov 18, 2022 reply Follow flag They should have asked max performance gain, it would be if programmed was sending data (1B in 100 micro sec) and interrupt was waiting for generation of data, so only the interrupt overhead (4 micro second) if interrupt also starts sending data, then it's time would be morr here and no speedup 0 0 replyShare goku4199 commented Oct 13, 2025 reply Follow flag Ans 4 4 replyShare Please log in or register to add a comment.
0 0 votes Ans goku4199 answered Oct 13, 2025 goku4199 comment Share Follow 0 reply Please log in or register to add a comment.
