Interrupt latency

This is the time that a computer system takes to begin running the interrupt code associated with a particular electronic event.

Most operating systems (OS) disable interrupts in order to protect their critical regions. Therefore interrupt latency is determined by the software of a computer system.

Interrupt latency and throughput are not the same. Many of the techniques that improve interrupt latency reduce throughput. For example, low-latency operating systems use special data structures that permit the OS to enable interrupts on each cycle of the search of the data structure. This reduces the absolute number of times that the OS can switch tasks per second (i.e., it lowers throughput), but decreases the OS's response time to service the electronics.

Many computer systems require low interrupt latencies, especially embedded systems that control machinery in real-time. Sometimes these systems use a real-time operating system.