In Realtime Operating Systems (RTOS), interrupt latency is the time between the generation of an interrupt by a device (or a peripheral) and servicing the device which generated the interrupt. For many operating systems (OS), the OS code is programmed so that devices are serviced as soon as the device's interrupt handler is executed. Interrupt latency depends on the CPU, interrupt controllers, interrupt masking, and the operating system's (OS) "interrupt handling methods".