Today I am going to tell you some of the advantages and disadvantages of using real time operating system. This is a type of RTOS tutorial. First of all we have to know what exactly an operating system do.
What is an operating system:-
An operating system hides all the difficult computation with the hardware which software do on the backend. We are presented a computer screen that we can work on and all other details that is the communication between software and hardware is hidden form us. So an operating system is a type of software which communicates between application software and hardware.
What is real time operating system:-
A real time operating system is the type of system which uses maximum time and resources to output exact and on the time result. There is no difference between the results when same problem run on different occasion on same machine. There is no late or early execution on that operating system and is done on fixed time as suggested.
RTOS is used for automatic system for example the robots machines that are manufacturing cars. Also RTOS are used in aircrafts i.e. during launch of aircraft on space and landing of aircraft. Also the other tasks and operation done by aircraft on space is controlled by the RTOS.
Real time operating system types:-
There are two main types of RTOS. Soft RTOS is a type of system which is less strict to time and accuracy and hard RTOS is another type which show exact execution time and exact output and results on required time.
Jitter is a term used for the amount of errors and gap between subsequent loops and operation of same task i.e. suppose if four same tasks are run in a loop then the time gap between completion of these tasks or the difference in time of execution of each task is known as jitter. So in soft RTOS there is some jitter found while in hard RTOS there is no or very little chance of Jitter.
Real time operating system are usually event driven and strict. For example these operating system have to response immediately when some event or interrupt occurs.
As we have now understanding of what is an operating system and RTOS so let us move to our topic.
Advantages of Real Time Operating System:-
There are some of the features of using RTOS that is described below
Maximum Consumption: – RTOS give maximum consumption of the system and gives us more output while using all the resources and keeping all devices active. There is little or no down time in these systems. So it can be also using by the servers that are hosted to give maximum output of hosting companies.
Task Shifting: – There is very little time assigned to shifting tasks in these systems. For example in older systems it takes about 10 micro seconds in shifting one task to another and in latest systems it takes 3 micro seconds.
Focus on Application: – These type of operating system focus on applications which are running and usually give less importance to other application residing in waiting stage of life cycle. So less applications or tasks are managed and give exact result on current execution work.
Real time operating system in embedded system: – Due to small size of programs RTOS can also be used in embedded systems like in transport and others.
Error Free: – RTOS is error free that mean it has no chances of error in performing tasks.
24-7 systems: – RTOS can be best used for any applications which run 24 hours and 7 days because it do less task shifting and give maximum output.
Real time operating system examples: – There are many real time operating system examples. They are used in vast areas like digital appliances, home video games, wind power systems, intelligent transport system, and robots in industry
Memory Allocation: – Memory allocation is best managed in these type of systems.
Disadvantages of Real Time Operating System:-
There are some disadvantages of RTOS also. So every system has pros and cons so here are some of bad things about RTOS.
Limited Tasks: – There are only limited tasks run at the same time and the concentration of these system are on few application to avoid errors and other task have to wait. Sometime there is no time limit of how much the waiting tasks have to wait.
Use heavy system resources: – RTOS used lot of system resources which is not as good and is also expensive.
Low multi-tasking: – Multi tasking is done few of times and this is the main disadvantage of RTOS because these system runs few tasks and stay focused on them. So it is not best for systems which use lot of multi-threading because of poor thread priority.
Complex Algorithms: – RTOS uses complex algorithms to achieve a desired output and it is very difficult to write that algorithms for a designer.
Device driver and interrupt signals: – RTOS must need specific device drivers and interrupt signals to response fast to interrupts.
Thread Priority: – Thread priority is not good as RTOS do less switching of tasks.
Expensive: – RTOS are usually very expensive because of the resources they need to work.
Not easy to program: – The designer have to write proficient program for real time operating system which is not easy as a piece of cake.
Low Priority Tasks: – The low priority tasks may not get time to run because these systems have to keep accuracy of current running programs.
Precision of code: – Event handling of tasks is strict so more precision in code needed for designer to program. Event must be responded quickly and this is not easy for exact precision for the designer.
Other factors: – There are lot of factors needed to consider like memory management, CPU and error handling.
In this tutorial article we have discussed advantages and disadvantages of Real time operating systems. Some of these we have already discussed. There are some other detailed and complex problems also which is not appropriate for this topic.