Interrupts are the signals userland process want to take ownership of CPU for a while(time is very short about milliseconds) to work on its requests via a system call. When this happens, in the single core situation, CPU based on priority and scheduling algorithm to determine whether put the process to the ready queue or keep it running.
There are software interrupts and hardware interrupts to differentiate this interrupts triggered by which components. But too many interrupts will significantly degrade the performance without a doubt. Some time hardware interrupts even got worse if it kept at a high rate. Let’s do a real case review as an example, but before doing that, first, we will review some knowledge about interrupts.