Polling means that we are continually using CPU cycles to check whether any I/O is occurring or not.
However, it means the CPU is busy-waiting on any other task so as to not miss any I/O. Interrupt-driven
I/O allows the CPU to work on other tasks and handle requests on demand, however it requires a
context switch into the interrupt handler to process it. We normally favour interrupt-driven I/O for any sort of human interface device, as it is much slower than the data processing it is doing, so a few hundred
interrupts each second won’t matter. We might favour polling for high bandwidth raw data transfer
applications, as a million context switches tends to slow things down.
Titany answered the question on April 26, 2022 at 13:23
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