<P> A key characteristic of an RTOS is the level of its consistency concerning the amount of time it takes to accept and complete an application 's task ; the variability is jitter . A hard real - time operating system has less jitter than a soft real - time operating system . The chief design goal is not high throughput , but rather a guarantee of a soft or hard performance category . An RTOS that can usually or generally meet a deadline is a soft real - time OS , but if it can meet a deadline deterministically it is a hard real - time OS . </P>
a required characteristic of an online real-time system is
the level of its consistency concerning the amount of time it takes to accept and complete an application 's task