Question

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What is a real-time system? What do we mean by hard and soft real-time systems?

Discuss, based one real-time operating system and one general purpose operating system, the differences between a real-time operating system and a general-purpose operating system.?

Answer 1

Real Time system:

Systems whose correctness depends on their temporal aspects as well as their functional aspects .(or) The ability of operating system to providee in a bounded respopnse time.

Hard real time system:

A hard real time system has time crictical deadlines that must be met, otherwise a catastrophic system failure can occur.

Soft real time system:

A soft real time system it considered undesirable, but not catastrophic, if deadlines are occasionally missed.

Real time operating system

Most of the embedded systems are bound to real time constraints and it is achieved using real time system .

In embedded system can give accurate output at right time ,It has no time delay.Example Air bag in car when accident happend in fraction of seconds the air bg opens at high spped there is no time delay .

General purpose operating system:

General purpose operating system are suitable to do multiple tasks at the same time.The behaviour of general purpose machine depends upon the nature of application design. A general purpose operating system designed to handle multiple task with no limt of time. Example Pc copy of data from folder to another folder takes time we can't predict .

REAL TIME	GENERAL PURPOSE
1.synchronization is achieved .	1. Synchronization can't be achieved
2.real time kernel follows preemptive scheduling policy	2.General purpose follows non preemptive scheduling polciy
3.Inter task communication is done	3. inter task ca't done.
4.The mathematical relation can be defined	4. Mathematical relation ca't be defined